tweets:, external Probably illegal under election law, but wouldn't it be interesting to subject all party election broadcasts to the @C4Gogglebox, external treatment?

Lib Dem campaign correspondent Chris Buckler is on the party's battle bus. "According to gossip on board it has in the past served as transport for both the French rugby squad and Crystal Palace. The Lib Dem team started the campaign journey with a kind of caretaker manager in Lord Ashdown, while Nick Clegg was busy at Buckingham Palace. The party's former leader was obviously happy to be back on the campaign trail and refreshingly frank with the press pack. In response to questions about the poor state of the party in the polls, Paddy Ashdown pointed out that he led the Lib Dems at a time when their support was marked by an asterisk, indicating something less than 1%. And he confessed he had watched Channel 4's "brilliant" drama Coalition on Saturday, although he thought the film portrayed him a little too much like Yoda."

Image source, AP

A day for firsts. And here's 16-year-old Ewan Rowe, from Solihull, securing one of the first selfies of the campaign trail with Nick Clegg.

Image source, PA

Labour's Chuka Umunna tells BBC Radio 5Live Drive Conservative claims families will be more than £3,000 worse off under Labour are "complete and utter garbage".

Tim Reid, BBC Scotland political correspondent writes: "At least a dozen former MPs have ignored House of Commons guidance to make clear on their social media profiles by today that they are no longer members of parliament now that it has been dissolved.

"No one is allowed to use the title member of parliament while the official general election campaign is ongoing. But at least a dozen former members who are candidates are still continuing to do so. The House of Commons advised MPs to alter their social media accounts or to add a disclaimer stating that the account was created when the candidate was an MP. The Electoral Commission has said it is not something which it can enforce."

Carole Walker, the BBC's Conservative Campaign Correspondent, writes: "David Cameron tells first campaign rally he's fighting on his record, his team and his economic plan for the country.

"Conservative sources say they stand by the claim that Labour would cost working families £3000 in higher taxes but David Cameron did not mention it in his speech to his first campaign rally."

The Lib Dem president Sal Brinton says she has "every confidence" that the party leader Nick Clegg will win his seat. Asked by the BBC's Ross Hawkins if she would be the one to negotiate any coalition deal in the event of a hung parliament, she said: "No - and the premise of that question is wrong".

She added: "Nick Clegg is not going to lose his seat. We are pretty confident of that. Campaigning in Sheffield Hallam is going extremely well, despite Labour gains on that." She added that the party had put together a "coalition negotiation team", which was not going to meet until 8 May.

Most opinion polls are suggesting a hung Parliament, and that could mean two or more parties having to work together after 7 May. The BBC's Christian Fraser and Jo Coburn use touch-screen software to look at what the polls are saying, and how Scottish results could play a key part at the coming general election. Watch the Daily Politics clip

Image source, bbc

Daily Politics
Live on BBC Two

Parliament has been dissolved and the previously-elected MPs lose their titles and privileges until they, or their successors, are elected after 7 May. BBC Parliament's Daniel Brittain explains the legal details of what happens now to ensure that election writs are issued to all 650 constituencies, as he hears about the legal documents and their seals. Watch his film

Chris Leslie, from Labour's treasury team, hit out at George Osborne's comments to Huw Edwards in the past hour, saying: "What planet is he on? He does not seem to realise he has broken most of his promises over the last five years." Asked by Ross Hawkins to say what taxes Labour would levy, Mr Leslie said: "They will have to be fair. For us, it has to be the richest 1%."

Peter Hunt, the BBC's Labour Campaign Correspondent, reports on the start of the party's campaign, for a feature called 'On the leader buses':

While David Cameron undertook a symbolically helpful, but constitutionally unnecessary journey to the Queen - to tell her Parliament was being dissolved - Ed Miliband faced a more challenging task. He was launching his party's business manifesto. Their focus is on "responsible" capitalism and the risks of leaving the EU. Their critics have accused them of having a "sneering hatred" of business.

In the coming weeks, Labour will attempt to move the debate onto more fertile ground, from their perspective. Expect plenty of talk about the NHS, tuition fees and freezing energy prices. Expect rather less unprompted talk about immigration; the failures of the last Labour government; and on how they'd cut spending if they succeed.

And also expect an unremitting focus on the character of the man who destroyed (for now) his brother's ambition. Does the Labour leader have the vision? Can he be trusted with the economy? Has he connected with the electorate?

On television, in marginal constituencies and at photo opportunities political parties never tire of creating, Ed Miliband will be on display.Voters will be able to observe and then pass their judgement.

"Britain is walking tall again," the Chancellor George Osborne tells Huw Edwards outside number 11 Downing Street. He says people have to vote for what they want - and for who they want to see in number 10.

"I think the election will focus people's minds and when they see that stark choice they are going to vote for David Cameron," he said.

Mr Osborne said the Conservatives stood by their view that a Labour government would add £3,000 in tax to a working family.

Most Americans will find it strange that British MPs have to give up their office and political titles as they stand for election, says Anthony Zurcher, our North America reporter. "In the US members of Congress retain their positions during the campaign and even for two months after election day. Sometimes they're called back to Washington for "lame duck" post-election sessions to vote on major legislation - even if they've been defeated or are soon to be retired. I explain it all in my latest campaignspotting blog post. "

Labour's Diane Abbott has clarified her position regarding her earlier comments on Labour's immigration pledge. She said: "I am not against immigration controls in principle...We've always had immigration controls....I am against trying to out-UKIP UKIP". Yesterday, Ms Abbott tweeted that a promotional mug setting out the party's immigration policy was "an embarrassment". She added the "real problem is that immigration controls are one of our five pledges at all".

In a blog, the head of news at Five Live Steve Mawhinney outlines the network's plans for the election. He says at its heart "will be an ambitious plan to host 20 programmes across 20 weekdays in 20 of the key marginal seats around the UK".

"From Fermanagh to Thanet, Cardiff to Dundee, Stockton to St Ives, we will be aiming to get to the heart of what you really care about and finding out how that will shape the way you vote," he writes.

Image source, BBC News

In Scotland, the political parties are also hitting the campaign trail. Key figures from Labour and the SNP were in Glasgow's east end while the Liberal Democrats were out in East Dunbartonshire. Scottish Conservative leader Ruth Davidson began her campaign in Edinburgh and the city was also the venue for the Greens' manifesto launch. In Westminster, Parliament was formally dissolved after the Prime Minister had an audience with the Queen and in Edinburgh, a proclamation was read out at Mercat Cross, telling voters that a general election had been called.

Andrew Neil
Daily and Sunday Politics

Watch the first of a series of daily films running throughout the election campaign as Andrew Neil has the political headlines.

Liberal Democrat campaign chief Lord Ashdown says he would like the party's opinion poll ratings to be higher but insists voters will decide the outcome of the election based on a "sober-minded" assessment of the challenges facing the country. The former party leader said the single-figure poll ratings were not as bad as those the party had in his time in charge and predicted the gap between the Lib Dems and their rivals would narrow. Speaking to reporters on the party's election battle bus he said the Lib Dems were running a "highly targeted strategy" and predicted the tight contest would go "to the wire".

Image source, PA

The UKIP leader, Nigel Farage, says he is "concerned" about the safety of some of the party's election candidates. He has asked for state-funded security for himself after being repeatedly targeted by protesters. "I think this will be a rough election campaign," he said.

"I'm less fearful for myself but I'm concerned about some of our other candidates both at local level... and standing in the general election. There is, I'm afraid, something of a trade union-funded hate mob out there that have decided UKIP are a series of things we are not."

The Mayor of Calais Natacha Bouchart has said migrants in the French town want to travel to England because "they can expect better conditions than anywhere else in Europe or even internationally". In an interview with the Council of Europe's Journal, she claims access to social welfare support "that doesn't exist in other countries" is a key factor.

The mayor is critical of Britain's approach, claiming Calais had been left to deal with the influx of thousands of migrants, saying: "The main problem is that the migrants that arrive in Calais don't want to ask for asylum. They want to travel on to England. .. There are no ID cards. They can easily find work outside the formal economy, which is not really controlled."