Leaders of Lebanon’s U.S.-backed government and the Hezbollah-led opposition are sitting down behind closed doors.

They’re sitting down in Qatar for the highest-level talks so far in the 18-month political crisis.

The Doha-hosted meeting on forming a national unity government and electing a president was agreed under a deal between feuding factions to end Lebanon’s worst violence since the 1975-1990 civil war.

Telecommunications Minister Marwan Hamadeh told The Associated Press from Qatar that the talks will also discuss “Hezbollah’s use of its weapons to achieve internal political aims” in the wake of recent violence.

He expects “three critical days” before the sides reach any sort of compromise on the standoff.