Senior Tory MP Michael Ancram has called for dialogue with Hamas - the Islamist movement boycotted by the West for refusing to recognise Israel.
Mr Ancram said Hamas would have to be engaged with eventually
Talking to Hamas, which seized control of Gaza in June, had already helped to free BBC journalist Alan Johnston, he wrote on the Conservative Home website.
He wrote that starting an "exploratory dialogue" had opened "vital windows" with the IRA, 15 years ago.
Meanwhile 39 MPs have signed a motion calling for engagement with Hamas.
Hamas, which is seen as a terrorist organisation by Israel, the US and the EU, has been engaged in a power struggle with its secular nationalist rival Fatah - led by Palestinian Authority President Mahmoud Abbas.
The Commons motion was tabled by Labour MP Richard Burden.
It has been signed by Labour MPs, including former Northern Ireland secretary Paul Murphy, SNP leader and Scotland's First Minister Alex Salmond, Lib Dem frontbencher Vincent Cable and senior Tory backbencher Nicholas Soames.
It says Hamas' role in freeing Alan Johnston shows why "the international community's support for Mahmoud Abbas as the legitimate President of Palestine should not preclude contact with Hamas".
Writing for Conservative Home, Mr Ancram - a former shadow foreign secretary - said it was not possible to argue for a "two-state solution" without engaging "all the relevant Palestinian elements".
He said it was "fantasy" to believe Hamas could be eradicated and "sooner or later" the group would have to be engaged with.
He said that he understood why Israel - which Hamas has refused to recognise - could not talk to them, it did not mean that "others should not begin the process of exploratory dialogue with them".
The former Northern Ireland minister added: "A process which as I personally know, opened vital windows for us with Irish republicanism in similarly intransigent circumstances fifteen years ago."
Alan Johnston recognised the role of Hamas in his release
"If it's right, as undoubtedly it was, to talk to Hamas to help free Alan Johnston, how can it be wrong to talk to them in the cause of freeing the Middle East from violence?"
He said that while Hamas had not met the conditions for engagement outlined by the Quartet of Russia, EU, America and UN - legally recognising Israel, ending violence and accepting previous agreements - Hamas had gone "a very long way towards the spirit of it".
But last week the Israeli foreign ministry spokesman Mark Regev rejected the idea that Hamas had implicitly recognised the existence of Israel and would accept a Palestinian state standing alongside it.
He told the BBC that while he accepted the existence of Aids, he would still like to destroy it.