Tony Blair is to give evidence before a parliamentary investigation into the On The Runs (OTRs) scheme for fugitive IRA members, an official confirmed.
The former prime minister's Labour administration sent about 200 letters to republicans assuring them they were not being pursued by the UK authorities following requests from Sinn Fein.
An investigation was launched by MPs when the prosecution of a man for the murder of four soldiers during an explosion at Hyde Park in 1982 was halted after he received one of the letters in error.
The OTR letters scheme began while Mr Blair was premier and the chairman of the Northern Ireland Affairs Committee has said he is one of the most important witnesses to the inquiry.
A spokesman for the committee said Mr Blair had confirmed he would be attending a sitting on Tuesday January 13.
Mr Blair was a key architect of the Good Friday Agreement, which led to IRA arms decommissioning and the establishment of a devolved power-sharing administration at Stormont.
He has been summoned to be questioned about how his government dealt with paramilitary suspects in crimes committed during Northern Ireland's 30-year conflict from 1969 to 1998, when the Agreement was signed.
His administration began a peace process scheme in 2000 which saw 95 of the so-called letters of comfort issued by the Government to suspects linked by intelligence to almost 300 murders.
They told people they were not wanted at that time but did not rule out future prosecutions if new evidence became available.
The scheme was drawn up following pressure from Sinn Fein to allow the fugitives, who, had they been in prison before 1998 would have been released under the Good Friday Agreement, to return to Northern Ireland.
The Northern Ireland Affairs Committee launched its investigation after John Downey was released last year when a judge halted his prosecution for the Hyde Park bombing.
Household Cavalry Lieutenant Anthony "Denis" Daly, 23, died in the explosion in Hyde Park on July 20 1982 alongside Trooper Simon Tipper, 19, Lance Corporal Jeffrey Young, 19, and 36-year-old Squadron Quartermaster Corporal Roy Bright.
Former Northern Ireland Secretary Peter Mandelson has said the issue of on-the- runs started the day he was appointed in 1999 and mainly concerned Sinn Fein's Rita O'Hare.
Ms O'Hare, the party's representative to the United States, is one of the most high-profile fugitive republicans, having skipped bail to the Irish Republic in 1972 after her arrest in connection with the attempted murder of a soldier.
Sinn Fein has argued that those covered by the letters scheme supported the peace process.
Last year the Northern Ireland Affairs Committee complained Mr Blair in effect had "refused" to appear before the inquiry in person to answer questions about his government's role.
Committee member Ian Paisley, DUP MP for North Antrim, said: "It is vital that we get to the bottom of the grubby deal struck between the previous Labour government and republicans."
He added: "It would have been a contempt of Parliament for him not to attend and this demonstrates the power of the committee."