Labour sources have accused David Cameron of trying to "pull a fast one” and spend taxpayers money on propaganda in the weeks leading up to the European Union referendum.

Party insiders claimed the Prime Minister was trying to redefine 'purdah', the Whitehall convention that restricts government announcements in and around polling days.

Earlier Mr Cameron's government had announced a climbdown on plans to suspend purdah for the EU vote.

The about turn came after it emerged the Tory leader faced a backbench rebellion among 40 of his own MPs.

With a Commons majority of just 12, Mr Cameron risked suffering his first major Commons defeat since May’s General Election on the issue when MPs vote next Monday.

Labour claimed victory saying that the Conservatives had effectively accepted their arguments on purdah.

A "business as usual" provision will still allow minister to comment on European business, in a move supported by Labour.

The SNP’s international affairs spokesman Alex Salmond claimed that Mr Cameron had lost control of the referendum.

Earlier this week the Conservative leader was forced to change the question that will be asked.

The Electoral Commission, the UK's elections watchdog, ruled against a choice that would require the electorate to back either Yes or No.

Instead voters will be asked to tick one of two options - either to remain in the EU or to leave the EU.

Confirming the government's change of heart on purdah, Tory Europe Minister David Lidington said ministers were determined to "take into account concerns about activity in the final four weeks before the referendum".

In June Mr Cameron survived a Commons revolt of 27 Tory MPs - including five former cabinet members - protesting at plans to drop the 28-day purdah period.

The SNP plans to press ahead with its own amendment designed to ensure ministers cannot ignore the purdah rule.

Mr Salmond accused the UK Government of brushing aside the convention in the run up to last year's independence vote.

"The SNP believe in a fair ballot, and we will not allow the Prime Minister to engage in the same chicanery in the Europe poll as he did in the Scottish referendum of one year ago," he said.