By Jonathan Davies

Liberal Democrat leader Nick Clegg has said it is vital that his party are part of the next government "stop it lurching off to the extremes".

Launching the Lid Dems' election manifesto, Mr Clegg said a vote for the party would stop the Conservatives or Labour from governing on their own, and would stop UKIP and the SNP from getting into government and 'holding the balance of power'.

The Lib Dem leader said the party's "gutsy" decision to form the coalition with the Conservatives had been vindicated by the economic recovery. He added that the party would "add a heart to a Conservative government and add a brain to a Labour one".

Announcing the party's five-key manifesto pledges, Nick Clegg said it was a "programme for government, not opposition".

The Lid Dems want to reduce the deficit fairly - it plans to cut less than the Tories, but borrow less than Labour. The party also pledges to provide £2.5 billion of extra funding for education, raise the tax-free personal allowance to £12,500, invest £8bn in the NHS and boost mental health treatment and car, and introduce five environmental laws relating to nature and climate change.