Ex-premier Saad Hariri has said his bloc is prepared to form a government with Hezbollah to resolve Lebanon's months-long political deadlock, although they back opposite sides in the Syrian conflict.
The shift by Hariri, who heads the so-called March 14 coalition, comes despite a Beirut car bombing last month that killed a Hariri adviser, Mohammad Chatah, and was blamed by his bloc on Syrian-backed Shiite movement Hezbollah.
Hariri, in an interview with his Future TV broadcast late on Monday, also stressed that Hezbollah ministers in any future government he heads must not have veto powers.
For nine months, since the resignation of prime minister Najib Mikati, Lebanon has been in political paralysis, with March 14 and Hezbollah and its allies unable to agree on a new government.
Chatah's was the latest in a string of assassinations in Lebanon of anti-Damascus politicians that began in 2005, with the killing of Saad Hariri's father, Rafiq Hariri, another former premier.
"We have been targeted with assassinations for nine years, and we have waited and waited. But will we wait for the country to burn down?" Hariri told Future TV.
"I have made this decision (to accept forming a government with Hezbollah) for the sake of Lebanon's interests, rather than my own," Hariri added.
But, he said, "I will not accept (that Hezbollah hold) the veto-wielding third" of posts in a future cabinet.
Hariri also stressed he would not allow a future government to provide cover for Hezbollah's role in the war in neighbouring Syria, and that he would insist Lebanon remain neutral.
"Yes, I am marching with the Syrian revolution... but the difference between me and others is that I am marching politically. I am not sending thousands of soldiers," said Hariri.
He was referring to the thousands of fighters which Hezbollah has sent into Syria to battle alongside regime troops against the mostly Sunni rebel forces.
Hariri, exiled in France since 2011, has said he will return to Lebanon for legislative elections scheduled for November.
Syria dominated Lebanon politically and militarily for 30 years until 2005, when an international outcry over Rafiq Hariri's killing forced Damascus to withdraw its troops.
The Future bloc leader's statements follow last week's opening in The Hague of a trial in absentia of four Hezbollah members over Rafic Hariri's assassination.
Syria's President Bashar al-Assad at the weekend described the trial in an interview with AFP as a "tool" to pressure his Hezbollah allies.
Hariri slammed the claim, saying: "Oh, so Assad is as transparent as they come?... He's killed 200,000 people (in Syria) and he gave the order to assassinate Rafiq Hariri."
He said he hoped the Hague-based court would indict the Syrian head of state over his father's killing.