In his speech, Mr McDonnell also outlined plans to:

• give employees a strong stake in the business they work for
• introduce an Excessive Pay Levy on companies over disparities in pay between senior executives and other employees
• require companies set out their policy for tackling the gender and ethnicity pay gap
• an overhaul of the UK's system of regulation, including establishing its only regulatory bodies

Tom Barton
BBC Look East political reporter

The Greens tell us they want to reform the UK’s “disgustingly unfair” first-past-the-post voting system. Under the current system, the candidate with the most votes in a constituency becomes the MP. But if a party comes a close second in several constituencies, there is no recognition for all those voters..

In 2017 the Green Party won more than 500,000 votes, but had just one MP elected, the party points out.

Voting reform is a cause celebre of smaller parties across the political spectrum and is perhaps the only issue that unites the Liberal Democrats and the Brexit Party.

They argue they are motivated not simply by self-interest, but by a desire to ensure a full spectrum of views is represented in Parliament.

The public has been asked what it thinks about one proposal, introducing the alternative vote system - under which voters would rank candidates - at a referendum in 2011. However, 67% voted against change.

But a lot has happened in UK politics in the last eight years, and the Greens are likely to propose a markedly different voting system.

John McDonnell says: "We believe a new business model is needed.

"At the heart, we believe that every business should be a partnership - between employees, customers, managers and shareholders - for the long-term success of the enterprise.

"Many European countries have more robust systems to secure long term decision making than the UK.

He adds that, if Labour gain power, it will rewrite the Companies Act "so that directors have a duty to promote the long-term interests of employees, customers, the environment and the wider public".

John McDonnell says the Labour Party is launching a report on its plans to rewrite the rules of the economy. "It's a summary of some of our ideas," he says.

He begins his speech by saying that workers often have no say over the places that they work - that major decisions about the operation and future of their firms are often made without them having a voice.

Mr McDonnell says Labour's plans "are about treating people fairly and with the respect that they deserve". He says Labour's reforms will help workers to "take back control".

He adds that the report includes "extensive work" that Labour has undertaken on a reform model, which will "lay some of the foundations of a stakeholder economy".

In an interview with the Evening Standard,, external ahead of tonight's TV debate, the prime minister promises that new measures to combat knife crime will be included in the Conservative manifesto.

These measures include:

• Faster charging and prosecution times of knife offenders. Anyone caught with a knife will be arrested, charged within 24 hours and in court within a week, the Conservatives will promise.
• A new form of court order called a serious violence reduction order, allowing police to search habitual knife carriers in the street without requiring suspicion.

“Increased powers to stop and search has had a transformative effect in the past year so we will extend those powers further to help the police catch more criminals carrying weapons. We will also speed up prosecutions so that the threat of being caught is always an effective deterrent," Mr Johnson tells the Standard.

For those who don't know, the Evening Standard is a newspaper that covers London - where there has been a particular political focus on the problem of knife crime.

Shadow chancellor John McDonnell is now giving a speech in Westminster on the Labour Party's plans for the economy.

He begins by saying that "Labour will rewrite the rules of our economy".

We've been discussing how the party leaders are preparing for tonight's debate on ITV - for Jeremy Corbyn, it's with a trip to the barbers.

He's posted a clip on Instagram, saying he's having a "quick trim" before the first debate.

Confused by the latest election developments? Got a question about polling or policy? Or is there anything else you'd like us to explain?

Send your questions to BBC News via the form on this page and we'll do our best to answer them.

Today we have been answering questions specifically about education, like this one from Bill Coombes from Wells-next-the-Sea:

Q - If Labour cancel tuition fees for university students, what happens to fees owed by ex-graduates?

A - Universities in England can currently charge up to £9,250 a year in tuition fees, external, which can be paid for through a student loan. Recent figures indicate, external that the average debt among students who finished their courses in 2018 was £36,000.

The Labour Party has pledged to scrap tuition fees for university students in England, as have the Green Party, external. The Brexit Party has said it will scrap interest charges on tuition fees.

Both the Conservatives and Liberal Democrats have yet to outline their plans. But none of the main parties have suggested that outstanding fees or loans should be refunded or cancelled.

Scottish students at universities in Scotland do not pay tuition fees. They receive bursaries and loans to pay living expenses. Students from other parts of the UK are charged tuition fees if they attend university in Scotland.

Students at Welsh universities are charged tuition fees. And Welsh students, wherever they study in the UK, can also receive financial assistance - with living costs - from the Welsh government.

Universities in Northern Ireland can charge up to £4,275 a year for students from Northern Ireland, but up to £9,250 for those from England, Scotland and Wales. Students from Northern Ireland can apply for student loans to go to university anywhere in the UK.

You can read more questions on education here.

As part of our coverage of how the election is unfolding in Southampton, BBC Education Editor Branwen Jeffreys will be looking at some of the issues voters are most interested in on the BBC news channel today at 11:00.

So with the Green manifesto launch complete, much of today's political energy will be spent on previewing the first TV debate of the campaign - pitting Boris Johnson against Jeremy Corbyn on ITV, in that crucial hour before the latest edition of I'm A Celebrity... Get Me Out Of Here.

Former Gordon Brown adviser Theo Bertram and former Scottish Labour leader Kezia Dugdale have both posted threads on Twitter giving us a rundown on what it is like preparing for TV debates, ahead of tonight's face-off between Boris Johnson and Jeremy Corbyn.

The final piece of advice from Theo Bertram? "If you're not enjoying it, no-one else will."

Ms Dudgale, of course, could double up today and offer advice to the I'm A Celebrity contestants, having ventured into the Australian jungle two years ago.

And if you want to hear more from the Greens - and see their pledges being put under the microscope - co-leader Jonathan Bartley will be on a BBC Ask The Leader special tomorrow evening at 22:45 on BBC One and the BBC News Channel.

Hosted by Victoria Derbyshire, Mr Bartley will answer questions from voters.

With the launch complete, you can now pore over the full Green Party manifesto, external online.

The key pledge is to invest over £100 billion a year in a Green New Deal to reduce carbon emissions to net-zero by 2030 - 20 years before the current government target.

That includes funding heating upgrades for a million homes a year and the creation of 100,000 new energy efficient council homes annually. The party also says it will plant 700 million trees, fund new green transport and support renewable energy.

The manifesto's other headline pledge is to introduce universal basic income - an "unconditional" payment to everyone "at a level above their subsistence needs".

Someone earning minimum wage and working 37.5 hours a week would see their income rise by 10% to 15%, the party says.

The Greens' co-leaders Jonathan Bartley and Sian Berry pose with deputy leader Amelia Womack (centre) after launching the party's manifesto in London.

The media was advised in advance that the two Green Party co-leaders and their deputy would speak for three minutes each - and the whole manifesto launch was duly wrapped up in under 10 minutes as the party suggested.

In between the two co-leaders, we heard from deputy leader Amelia Womack, who set out the party's stall on Brexit, saying the party is offering "offering the only way forward from the wreckage of the 2016 referendum".

She said: "A vote for the Green Party is the strongest vote you can cast to keep Britain in Europe."

Ms Womack said the party would not "overturn the votes of millions of our fellow citizens", use EU citizens as "political pawns" or "watch as Tory extremists drive our country off a cliff".

Instead, they will offer another referendum and "stand up for freedom of movement".

"We’ve been Remain since the start and we will be Remain until we win."

We are now hearing from Green Party co-leader Sian Berry.

She is outlining 10 pieces of legislation the party would introduce if elected into government. You can read more on those here.

Ms Berry says every Green MP elected in December will have these 10 bills in their in-tray "to hit the ground running".

"The future won't give us another chance to get the next two years right," she says.

She adds that the Greens have a "vision for the future of this country"

"Our 10 bills will make our vision a reality," she says.

Lots of talk this morning about "net zero carbon" - but do you actually know what it means?

"Net zero" means that any emissions are balanced by an equivalent amount from the atmosphere, according to the Energy and Climate Intelligence Unit, external.

The government passed a law earlier this year obliging the country to cut emissions to net zero by 2050. The Green Party says that, if it was in power, it would commit to reaching this target by 2030.

The actual terminology used by the government is "net zero" greenhouse gases, such as carbon dioxide, by 2050, according to the BBC's environment analyst Roger Harribin.

That means emissions from homes, transport, farming and industry will have to be avoided completely or - in the most difficult examples - offset by planting trees or sucking CO2 out of the atmosphere.

The government's advisory committee on climate change said in May that the UK should lead the global fight against climate change by cutting greenhouse gases to nearly zero by 2050.

Jonathan Bartley begins by introducing the party's headline manifesto pledge - to reach net zero carbon emissions in the UK by 2030., external

"Our planet is ringing the alarm," he says. "Hitting snooze simply isn't an option.

"We can't expect the climate emergency to go into reverse."

He adds that net zero pledges by the other major parties are "not good enough".

"We're racing ahead," he says. "We're the groundbreakers and the innovators.

"We are ready to remain and transform everything.

The Green Party of England and Wales has begun its manifesto launch at London Wetland Centre in Richmond Upon Thames.

Co-leader Jonathan Bartley is the first to take the podium.

We are also expecting to hear from co-leader Sian Berry and deputy leader Amelia Womack.