Labour’s shadow chancellor John McDonnell has said his party would effectively end the freeze on welfare benefits - but refused to set out how.

Mr McDonnell, a key ally of leader Jeremy Corbyn, said that the policy would be eradicated through a package of reforms.

Labour has come under pressure in recent days for pledging to scrap university tuition fees in England, including for the wealthiest students, but failing to promise to reverse a series of cuts to social security.

McDonnell said that Labour would make the freeze irrelevant, but refused to say whether or not he would unfreeze benefits.

He told the BBC's Andrew Marr Show: "We're putting £30 billion in over the lifetime of a parliament into welfare, we're reforming the whole process - ...and... the impact of these proposals will make the freeze irrelevant because we'll reform the whole process."

Mr McDonnell rejected the findings of the Resolution Foundation think tank that 78 per cent of Conservative cuts would not be reversed under Labour's plans.

"I think the proposals that we'll be putting forward on reform... will ensure that in effect we will be addressing this issue of how we reverse the benefit freeze itself,” he said.

He added: "I feel so strongly on this - we will deliver this in the first budget."

Meanwhile, Mr Corbyn came under fire for an interview with Sky News in which he passed up six opportunities to condemn the IRA.

Instead, the veteran socialist said he condemned "all bombing" during the conflict.

Asked if he could condemn unequivocally the IRA, Mr Corbyn said: "Bombing is wrong, of course all bombing is wrong and of course I condemn it."

Asked to condemn the IRA without equating it to the deaths caused by British security services, Mr Corbyn said: "And there were loyalist bombs as well, which you haven't mentioned.

"I condemn all the bombing by the both loyalists and the IRA."

Security minister Ben Wallace, a former army officer who served in Northern Ireland, said: "People up and down the country will rightly be outraged that Jeremy Corbyn won't unequivocally condemn the IRA for the bloodshed, bombs and brutal murders they inflicted on a generation of innocent people.

"Jeremy Corbyn has spent a lifetime siding with Britain's enemies, but he and his extreme views could be leading our country and representing it abroad - negotiating with 27 EU countries in just over two weeks' time.

"And it's the British people who will pay for this for generations."

Meanwhile, Mr Corbyn said a Labour government would deliver a "fair" immigration policy but refused to be drawn on whether or not the numbers coming into the UK would fall.

The Labour leader said that immigration would "probably be lower" but added that he did not want to make predictions.