A UN proposal to end heavy fighting in the city of Aleppo has been rejected by the Syrian government.
Under the plan, rebel-held eastern Aleppo would remain under opposition control if rebel fighters withdrew.
Foreign Minister Walid al-Muallem called the truce plan a violation of "national sovereignty" and rejected it during a meeting in Damascus with UN envoy Staffan De Mistura.
The envoy had suggested the government grant autonomy and recognise the local administration in rebel-held areas of Aleppo if jihadist fighters left the city.
But Mr Muallem said the state's institutions must be restored across the whole city because it was a matter of "national sovereignty".
"It is not acceptable at all to leave some 275,000 of our people as hostages to 6000 or 7000 gunmen. There is no government in the world that would accept that," the Syrian minister said
Mr De Mistura warned earlier this week that the government was chasing a "pyrrhic victory" in Aleppo if it did not arrive at a political settlement with the opposition.
On Sunday, eight children died in government-held western Aleppo after rebels hit a school, state media said. A teacher was also killed and at least 32 people were injured.
In the rebel-held al-Sakhour district, a family of six were killed by a barrel bomb, activists said. Local medics said they had suffocated to death because the bomb was laced with chlorine gas.
According to the UK-based Syrian Observatory of Human Rights, at least 103 people have died in rebel-controlled areas since the bombardment began on Tuesday, following a three-week moratorium.
Syria Civil Defence, a volunteer rescue service also known as the White Helmets, said there were 180 air strikes on east Aleppo on Saturday alone.
The World Health Organization says residents of east Aleppo are almost entirely without hospital facilities following the government's latest assault.