UKBA EU immigration
Tory rebels want tougher controls on EU migrantsReuters

David Cameron is locked in a fresh row with his own MPs after claiming that the level of immigration from Romania and Bulgaria had been "reasonable" and did not represent the "flood" some scaremongers predicted when controls were lifted this year.

The prime minister is facing a major rebellion over the government's Immigration Bill amid demands for it to extend controls on migrants from the two countries until 2018.

And his latest remark further angered rebels, one of whom said: "How on earth would he know if it's been reasonable. There aren't any figures available yet."

He said the comment was more evidence the prime minister was not treating the issue of immigration from EU states seriously enough and that what worried people was the longer term influx of migrants.

It appeared that the prime minister's comments had strengthened the resolve of his party rebels to force the issue with an amendment to the Immigration Bill on Thursday which could derail the entire legislation.

Cameron seemed to realise he had gaffed when, hours after making his claim on the BBC's Today programme, he admitted: "There aren't any official statistics. I haven't been looking at any unofficial statistics, but just from what I read and see and hear, I think that these numbers look, as I said this morning, reasonable".

It then emerged the government was tabling its own list of around 50 amendments to the Bill which only added to the row as rebels claimed it was a blatant attempt to stop the debate in its tracks as there would not be parliamentary time to debate them all.

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One Tory MP John Baron said it seemed clear the government was using parliamentary tactics to avoid a vote on the rebels' amendment.

"It is a real shame they are playing this parliamentary tactic. To keep putting off debate will do no good at all," he said.

The prime minister had previously been attempting to head-off a revolt by appealing to his rebels not to risk destroying the Bill by trying to force changes that were impossible under EU rules.

"We've done the extent of what we can do within the rules that were agreed by the last government," he said.

"I completely understand, and in many ways share the frustrations of colleagues who would like us to go further. We've paused the bill over Christmas and now I think we can see at the start of the year so far that there looks to be a reasonable level of migration and I hope we can make progress with the bill because it does so many other good things."

But it seems his plea had actually made matters worse by appearing to play down the issue.

The final attempt to delay the entire Bill by tabling a huge number of amendments also added fuel to the flames as the rebels re-grouped and sought ways to counter the government's tactics.

Whatever the final outcome, it is likely a key piece of government legislation will remain the source of serious divisions between Cameron and his backbench rebels which is certain to come to a head at some point.