The fighters were expected to head to Jarablus, a town in northern Syria shared by rebels and Turkish forces.
He added, however, that "humanitarian cases" would be allowed to evacuate on Monday.
Syrian government forces backed by Russian Federation have recaptured almost all of eastern Ghouta, which was the last major rebel enclave on the outskirts of Damascus, in a ferocious assault that began in February, marking a major victory for President Bashar al-Assad.
The UN humanitarian adviser for Syria called on Wednesday for access to the eastern Ghouta town of Douma, where he said some 80,000-150,000 civilians were "on their knees" after years of siege and fighting.
A total of 1,198 militants with the Islam Army rebel group and their families evacuated Douma in the capital Damascus' Eastern Ghouta on Tuesday toward a rebel-held city in northern Syria, state news agency SANA reported.
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Vanessa Trump, right and Donald Trump , Jr., left, together with their family at the 2018 White House Easter Egg Roll . The U.S. has since joined the United Kingdom and other countries and expelled 60 Russian diplomats of its own.
After the last batch of armed islamists left the towns of Jobar, Arbeen, Zamalka and Ayn Tarma on Saturday evening, the entire Eastern Ghouta came under the government control except for Douma, the largest and most densely-populated area in that farming belt. The rebels refused to say, however, whether they had surrendered.
Under the deal, Syrian state media said Jaish al-Islam would hand over heavy and medium-sized weapons and acknowledge the restoration of the Damascus government's control of Douma.
"Our position is consistent and clear", he said.
This deal was reached after marathon negotiations as the Islam Army would be the last rebel group to leave Eastern Ghouta after 43,000 rebels and their families left other areas in Eastern Ghouta since last week.
"The armed forces' formations, aided by allied forces, wrapped up military operations in Damascus Countryside's Eastern Ghouta, with full control established all over its cities and towns", said the statement.
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Since Feb. 19, more than 1,400 victims have been killed in attacks by the regime and its allies in Eastern Ghouta, according to local civil-defense sources.
The evacuations are part of a Russian-brokered agreement between the Assad regime and armed opposition groups.
A convoy of vehicles carrying civilians from eastern Ghouta to Al Bab district are seen in Aleppo in Syria on April 03, 2018.
The group, which is estimated to have many thousands of fighters, has previously insisted it will not leave Douma or accept "forced displacement" to another part of Syria.
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He was seen in another directly addressing members of Red Velvet, which commands more than 4.6 million followers on Instagram. Even leader Kim acknowledged that there had been "so much interest in whether I'd come to see Red Velvet or not".