The Irish man jailed for trying to kill British Prime Minister Margaret Thatcher in the 1984 Brighton bombing appeared in the House of Commons Tuesday with the daughter of one of his victims.

Monday was the 25th anniversary of the bombing while Tuesday was Thatcher's 84th birthday.

Former IRA man Patrick Magee held a public discussion with Jo Berry, whose father was one of five people killed in the bombing.

The IRA statement at the time said: 'Today we were unlucky, but remember, we only have to be lucky once; you will have to be lucky always. Give Ireland peace and there will be no war.'"

Magee said it is "always a challenge to share a platform with Jo. ... The challenge is, I'm sharing a platform with someone whose father I killed."

"I'm sorry that I killed Jo's father," he said, "and I wish there had been another way."

Jo Berry and Magee have been meeting since he was released from jail in 1999 as part of the 1996 Good Friday Agreement.

"It's an unusual friendship," she said. "We don't really have the words in the English language for it. He's someone who I actually admire for his ability to engage with me even when it's difficult, and (for) his commitment to working for peace now," she said.

"And yet I don't forget that he did kill my father, so it's a mixture."

"Forgiveness is a word I find very difficult to use. I prefer to use the word understanding," she said.

"I have understood his life and his choices and everything that's happened to him.

"I know that if I'd lived his life, I don't know whether I'd make those same choices or not. And in that moment there is nothing to forgive, there is understanding and there is empathy."

But she still remembers the shock of seeing him walk free. "When I first saw him come out of prison, I had an initial response. ... I wasn't expecting to turn on the telly and see Pat coming out of prison, and there was an initial response of: 'Ah, he's out. My father can never come back.'

The session was hosted by The Forgiveness Project, a British charity working on conflict resolution.