Image caption The OTRs letters scheme began while Mr Blair was prime minister

Former prime minister Tony Blair "in effect has refused" to appear at a parliamentary inquiry into so-called On The Runs (OTRS), MPs have been told.

The Northern Ireland Affairs Select Committee is holding an inquiry into government letters sent to more than 200 republican paramilitary suspects.

The letters emerged in February, when the Hyde Park IRA bomb trial collapsed.

The chairman of the inquiry, Laurence Robertson, told the Commons Mr Blair's response was "totally unsatisfactory".

Mr Blair's office said the former prime minister was in "ongoing correspondence with Mr Robertson about the committee's request".

'Power to summon'

Mr Robertson raised the issue as a point of order in the Commons on Wednesday.

Commons speaker John Bercow told MPs it was within the committee's formal power to summon Mr Blair as a witness, but added he hoped the power would not have to be used.

The OTRs letters scheme began while Mr Blair was prime minister and the chairman said he is "one of the most important witnesses" to the inquiry.

The letters were sent to republicans who were suspected of, but who have never been charged or convicted, of a paramilitary offence during the Troubles.

The recipients included County Donegal resident John Downey, who received a letter in error, telling him he was not being sought by UK police over the murders of four soldiers in the 1982 IRA Hyde Park bomb.

His trial was halted in February, when the judge ruled the existence of the letter meant his prosecution was an abuse of process.

'Written answers'

Raising the issue in the Commons on Wednesday, Mr Robertson said: "One of the most important witnesses is of course the former prime minister Tony Blair.

"Mr Blair has failed to offer us any date when he could come before the committee. He has not refused to do, but in effect, has refused to do by not offering any date.

"He has offered to submit written answers, which I'm sure you will appreciate is totally unsatisfactory," Mr Robertson added.

"Given the importance of this inquiry and given the sensitive nature of it, given what it means to people in Northern Ireland and indeed beyond, I wonder if you could advise the committee how we might proceed?" he asked Mr Bercow.

The Speaker replied: "It is of course open to the Northern Ireland Affairs Committee, which you so ably chair, to exercise its formal power to summon witnesses. But I hope that it will be possible to resolve the issue without recourse to that.

"You have made your point and exposed the issue publicly. I am sure that the former prime minister intends no discourtesy and will swiftly respond," Mr Bercow added.

A statement release through Mr Blair's office said:"No one should be in any doubt of Tony Blair's commitment and respect for the people of Northern Ireland and indeed he has already given evidence to the government's inquiry led by Lady Justice Hallett about this issue.

"We are in ongoing correspondence with Mr Robertson about the committee's request, given that he has refused to accept written evidence," it added.