Brussels, Belgium (CNN) -- NATO members agreed Thursday to take over enforcement of the no-fly zone over Libya, but stopped short of interpreting that mandate as a license to attack government troops who may be threatening unarmed civilians. "What we have decided today is that NATO will enforce the no-fly zone," NATO Secretary-General Anders Fogh Rasmussen told CNN's Wolf Blitzer from the organization's headquarters in Brussels. Under Thursday's agreement, NATO forces will be able to close air space to all flights except for humanitarian ones and will be able to use force in self-defense. NATO also has sent a directive to its military chain of command asking for a plan on how to execute an expanded role for enforcement of U.N. Resolution 1973, according to NATO sources. Under what some officials were calling "no-fly plus," NATO would be given more robust rules of engagement to ensure that civilians are protected, the sources said.
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All 28 NATO allies authorized a plan that includes civilian protection
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Transition to be complete by Sunday night, sources say
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Questions on rules of engagement remain to be worked out
Rasmussen said the issue did not represent a split in @placeholder over the mission.