But in Tripoli expectations are low.

None of the foreign powers engaged in Libya — motivated by commercial interests, geopolitical games or regional and ideological rivalries — have so far shown any willingness to back off.

Mr. Hifter has said he would participate in the conference, but has never shown a willingness to accept any deal that gives him less than full control of the country.

His main foreign sponsor, the United Arab Emirates, had urged him to keep fighting rather than accept a cease-fire, according to three diplomats familiar with the discussions.

Leaders of the United Nations-backed government in Tripoli have also shown a recent distaste for the need to compromise with Mr. Hifter, claiming that the new influx of Turkish support gave them the potential for military victory.

“Turkey will help us as much as they can to defeat the advance of Hifter’s forces,” Khalid Elmeshri, a top official of the provisional government, said in an interview on Thursday.

And Libyans fear that even if the international summit meeting produces a new cease-fire, it may be no more than a pause before a new escalation of the war.

Renewed fighting could be even worse, many Tripoli residents said, because it would be between professional soldiers and trained mercenaries, not Libyan amateurs.