tweets:, external Expect a battle between the coalition parties to claim credit for Swansea Bay lagoon announcement in #Budget15 - Both say it was their idea

Image source, Tidal Lagoon Swansea Bay Ltd

This was supposed to be the "greenest government ever", and George Osborne will aim to demonstrate that today by announcing the world's first tidal lagoon. Attention will be on the level of government subsidies for the turbines generating power in Swansea Bay. The innovative project is set to cost around £1bn, it's been reported, external, and in the long-run it's hoped it will establish a blueprint for six UK lagoons which could between them provide 8% of the UK's electricity needs over 120 years.

tweets:, external Budget day at Downing street

Image source, Other

tweets:, external There are two "big" announcements held back for the #Budget2015, I'm told. Unfortunately I wasn't told what they were

Image source, PA

One sector with high expectations today is the oil and gas industry. Sir Ian Wood, a key figure in the industry, has said this is "a watershed" Budget. They'll be looking for cuts to corporation tax, currently at 30%, and the 30% "supplementary charge". "I want the hardworking people whose livelihood depends on the oil and gas industry to know that the British government is standing alongside them - and we will do everything we can to help," the chancellor told the OECD last month. "We've already cut taxes - and if we need to we will do so again in the Budget." Our Scottish business/economy editor Douglas Fraser has more here.

BBC Radio 4

If you missed Simon Jack's, external business briefing on Today earlier, fear not - you can catch it again here.

tweets:, external But will be lots of small measures despite 'no gimmicks' - money for church roofs, end of paper tax return, 25m to tackle returning jihadis

tweets:, external So what do we expect? A bit more wriggle room for Osborne and raise in tax threshold prob the biggest things we know so far...

Steph McGovern on BBC Breakfast has been playing Budget bingo. Tune in to BBC1 and BBC News channel at 7:20 and 8:20 GMT to play along.

The newspaper front pages, unusually for a Budget Day, aren't all about tweaks to the chancellor's taxation and spending plans. That's because they've got hold of another story - the "death of the annual tax return", as the Telegraph puts it. Here's our full paper review.

Kamal Ahmed
BBC Business editor

Beyond the public finances, and market reaction to any 'giveaways' by George Osborne, there will be four specific issues that business will be watching out for. Read more here.

Ross Hawkins
Political correspondent, BBC News

We turned up at 5:30 this morning in Downing Street and there was a cleaner just outside sweeping the step and polishing the brass knobs. Frankly, polishing the political reputations, making them look shiny and lovely, will be the key role of this financial statement. It's not a long-term plan for this government - it's about making sure that voters, when they go into the ballot box, have a good view of what it's done.

It may be that low inflation means there's a little bit more money to spend. It may mean George Osborne can cut a little bit less in the next parliament and it may mean he can soften and take away some of the impact of the attack lines Labour have been putting to him.

Alex Stevenson
BBC News

Good morning - there's a lot riding on this pre-election Budget in political terms. It is the event, many Conservative supporters hope, that could win the election for the Tories. Despite all the restrictions of austerity George Osborne has managed to generate eye-catching headlines in the past - but today he has promised no "gimmicks" or "giveaways" and the opposition will make him face up to the fact he hasn't quite reduced the deficit as quickly as the coalition had hoped back in 2010. Labour will be under pressure, too, to credibly attack the government's approach. Today is a high-stakes occasion.

BBC Radio 4

Jonathan Portes, director of the National Institute of Economic and Social Research, tells Today that the biggest problem facing the economy is a lack of public and private investment. He welcomes more government money going into big public projects. Mr Portes also notes that the Italian government can borrow at even lower rates than the UK despite that country's troubled economy.

tweets:, external For Budget Day, #r4today live from a Reading factory (M4 corridor = 8% of British econ output.) Will spoil you with more data in the morning

tweets:, external Update: Lab lead at 2 - Latest YouGov / The Sun results 17th Mar - Con 34%, Lab 36%, LD 7%, UKIP 12%, GRN 6%; APP -20

Radio 5 live

Louise Oliver, of financial planning firm Piercefield Oliver, tells Wake Up To Money there has been some good news for savers recently with initiatives such as a rise in the ISA allowance. That has allowed more people to pay down debt and increase saving - aided by the lower cost of living. She would like today's Budget to include more help for small businesses, with more relief for business rates.

Radio 5 live

Rob Wood, of Berenberg Bank, tells Wake Up To Money that getting re-elected will be very high in George Osborne's mind so that he can remain chancellor. "Of course this will be political," he says. Mr Osborne does have some wiggle room to reduce the pace of spending cuts and to set out how the next Tory government could cut taxes by reducing spending.

Chris Johnston
Business reporter

Good morning and welcome to Budget Live with me, Chris Johnston, Victoria King and Alex Stevenson. We are with you right though until midnight tonight - it's going to be an exciting ride.