The seven-year-old Bana Alabed, who captured a huge following on social media, has gone silent on Twitter as government forces retake rebel held sections of her city.
Bana's Twitter account which posted videos and images of life inside the besieged city went quiet and was deleted on Sunday as the city underwent heavy bombardment from Syrian Government forces and Russian airstrikes.
Her last Tweet read: "We are sure the army is capturing us now. We will see each other another day dear world. Bye.- Fatemah #Aleppo."
The account, which had 100,000 followers and was shared with Bana's mother Fatemah, was deleted shortly afterwards.
Late last month she tweeted: "Tonight we have no house, it's bombed and I got in rubble. I saw deaths and I almost died."
The Syrian army and allied militia have advanced towards rebel-held areas of Aleppo's Old City, thrusting deeper into opposition parts of the city in a relentless attack which a military source said would be over in a matter of weeks.
A senior rebel official told Reuters rebel groups in Aleppo had told the United States they will not leave their besieged, shrinking enclave, responding to a Russian call for talks with Washington over their withdrawal.
But facing relentless bombardment and ground assaults, the rebels may eventually have no choice but to negotiate a withdrawal from eastern Aleppo, where tens of thousands of civilians are thought to be sheltering.
The army announced new advances, which were confirmed by a rebel official with the Jabha Shamiya group. The advancing forces may soon reach a strategically important eye hospital, the capture of which would threaten further gains near the Old City, the official said, speaking to Reuters from Turkey on Sunday.
Loud explosions were heard coming from eastern Aleppo as night fell, Reuters journalists in the government-held part of the city said. The Jabha Shamiya official said further advances may force a rebel withdrawal to the southwestern corner of their enclave. "The areas of Old Aleppo will be threatened to a great degree," said the official. "It is scorched earth."
The Russian Defence Ministry says Syrian governmental forces have taken control of 52 percent of eastern Aleppo and are now in control of over 30 of the city's neighborhoods.
The UN Security Council is due to vote on Monday on a draft resolution that would demand an initial seven-day truce in Aleppo, which could then be renewed. But it was unclear if veto-power Moscow would block the resolution.
-With AAP