Airstrikes targeting the besieged Syrian city of Aleppo have reportedly resumed.

At least three people were killed in attacks on the rebel-held eastern part of the city, according to the Syrian Observatory for Human Rights.

The renewed strikes come three weeks after Russia - an ally of Syrian regime forces - announced it would temporarily halt air attacks to allow rebels and civilians to leave the city.

Syrian state television suggested regime warplanes targeted "terrorist strongholds" and supply depots in Aleppo, Al Jazeera reports.

According to Associated Press, the strikes in Aleppo came as Russia announced a major new air offensive in Syria.

The new offensive will focus on targets such as ammunition depots and training camps in Idlib city and the central province of Homs, officials indicated. They did not mention Aleppo as a target.

Yesterday, Vladimir Putin spoke to US President-elect Donald Trump about the situation in Syria.

In a statement, the Kremlin said the two men "spoke of the need to work together in the struggle against the number one common enemy – international terrorism and extremism. In this context, they discussed issues related to solving the crisis in Syria."