A list of major developments this week as part of diplomatic efforts to end the Syrian crisis:

_ April 9 _ Syrian Foreign Minister Walid Moallem arrives in Moscow for talks beginning Tuesday.

_ April 10 _ Deadline for Syrian troops to begin withdrawing from population centers under a cease-fire plan brokered by U.N. and Arab League envoy Kofi Annan.

_ April 10 _ Syrian and Russian foreign ministers scheduled to hold news conference in Moscow.

_ April 10 _ Annan to visit Syrian refugees in Turkey.

_ April 11 _ Annan expected in Tehran to discuss Syrian crisis.

_ April 12 _ 6 a.m. deadline for total cease-fire under Annan agreement.