BEIRUT — Hundreds more Syrians left the rebels’ last foothold in eastern Aleppo in convoys of buses escorted by the Syrian Red Crescent and the international Red Cross today under a cease-fire deal brokered by Ankara and Russia.

The evacuations came as Moscow was hosting the foreign ministers of Iran and Turkey in three-way talks on Aleppo’s future and prospects for peace in Syria. The development followed a U.N. Security Council Resolution that was agreed on Monday night to send observers to monitor the exodus.

The talks in the Russian capital, however, are likely to be overshadowed by the assassination of Russia’s ambassador to Turkey the previous night by an Ankara policeman, who after killing his victim cried out: “Don’t forget Aleppo! Don’t forget Syria!”

Dmitry Peskov, the spokesman for Russian President Vladimir Putin, said that Ambassador Andrei Karlov’s murder plays into the hands of those who want to derail peace talks for Syria.

Russia and Turkey back opposite sides in the Syrian war — Moscow is a staunch ally of Syrian President Bashar Assad, while Ankara backs the rebels seeking to topple him.

The International Committee for the Red Cross said it has overseen the evacuation of 25,000 people from east Aleppo since rebels effectively surrendered the area to the Syrian government. The evacuations are part of the cease-fire deal earlier this month that returns all of Syria’s largest city and its former commercial capital to government control, after nearly six years of war.

Residents from eastern Aleppo and the Syrian opposition say the evacuation amounts to forced displacement. Months of devastating Syrian and Russian air raids that destroyed buildings, hospitals and schools in the enclave — and reduced much of eastern Aleppo to a landscape of rubble — left the residents with little choice but to flee.

Ingy Sedky, Damascus spokesman for the ICRC, said thousands more still await evacuation and operations would continue throughout the day.

The Britain-based Syrian Observatory for Human Rights said that more than 15,000 people, among them 5,000 opposition fighters, have left the enclave since last week.