Annan spoke after a meeting of EU foreign ministers in Brussels. France agreed to lead the U.N. peacekeeping mission through February with Italy then rotating into the leadership.
"Europe is providing the backbone of the force and I'm very encouraged by the commitments I have received at this meeting" Annan said.
European countries had been slow to promise troops for the effort because of concerns about the rules of engagement. But on Friday, EU countries agreed to provide 5,600 to 6,900 troops as well as ships and planes.
Annan called the truce on the border between Israel and Lebanon "very fragile." He acknowledged that work needs to be done to clarify the mission and rules of engagement.
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