The agreement breaks a political impasse since June elections
Lebanon's political opposition has agreed to join a unity government under Prime Minister designate Saad Hariri.
Hezbollah - a powerful Shia political and military organisation - says the opposition alliance it leads agreed to the move after talks on Friday.
The governing coalition is believed to have agreed to a number of concessions, ending the deadlock that has existed since June's parliamentary elections.
Mr Hariri is expected to formally announce the deal shortly.
The BBC's Natalia Antelava in Beirut says the concessions made by Mr Hariri are believed to give the opposition control of ministries it had been seeking.
Reports say the new arrangement will allow Mr Hariri's alliance to nominate 15 ministers, with Hezbollah taking 10 portfolios. The remaining five ministers would be picked by President Michel Suleiman.
Mr Hariri - who is also backed by the US - led what many described as an anti-Syrian coalition to victory in the elections five months ago.
Syria was a significant political player in neighbouring Lebanon for nearly 30 years until the death of Mr Hariri's father, Rafik, in 2005.
Saad Hariri has spent the time since then trying to broker a deal with the opposition to join a unity cabinet. But he has faced a number of disputes over details, specifically the division of ministerial portfolios.
One of the sticking points centred on demands by Michel Aoun, a Christian leader and Hezbollah ally who is seeking to keep the telecommunications ministry.
It is not yet clear if his demands are among the concessions agreed to by Mr Hariri.
Our correspondent said Mr Hariri is now expected to give the list of names to Mr Suleiman, and once those are approved, the government will be formed.
There had been growing international concern over the deadlock and its impact on regional security and the Lebanese economy.