Four Liberal Democrat MPs are calling for an investigation into the impact of the new 20 per cent VAT rate.
The MPs have tabled an amendment to the VAT section of the ways and means motion, calling for a further assessment of the impact of the planned rise and a vote in the House.
It follows the government's announcement in the Budget that from January 4 2011 VAT will increase from 17.5 per cent to 20 per cent.
However the amendment is unlikely to be put to the vote.
But the fact that it is on the Order Paper highlights the fears of some Lib Dem MPs about the social impact of the Budget.
Andrew George (Lib Dem, St Ives and the Isles of Scilly) proposed the amendment to the Finance Bill to register his concerns about the possible unfairness of the increase.
Three of his parliamentary colleagues – Bob Russell, Roger Williams and Mark Williams – have signed the amendment, which demands "an assessment of the impact of the increases it proposes upon business, charities and households across the income and age groups".
George said: "I am not trying to trigger nuclear war and break up the coalition, it's perfectly normal for two parties to have different approaches and values.
"I just want to express my unhappiness with the move and have an open debate."
The MP for St Ives also said he hoped a government minister would respond to the amendment and added he will continue to look for opportunities to highlight the case.
Writing in the Observer, Lib Dem chief secretary to the Treasury Danny Alexander admitted measures such as the VAT rise were proving unpopular with party members but insisted they were "unavoidable" given the state of the public finances.
Last week Lib Dem deputy leader Simon Hughes suggested his party may try to amend the Budget – although he subsequently said the comments had been taken out of context.


Have your say...
Please enter your comments below.