Foreign Minister Mevlüt Çavuşoğlu discussed the recent developments in Syria with the U.S. Secretary of State John Kerry in a phone call.According to ministry sources, the two top diplomats focused on the steps to be taken to deliver humanitarian aid to Aleppo and stop the ongoing bombings on the city's opposition-held areas.Russia has been accused of indiscriminately bombing Aleppo's opposition-controlled east as it helps an assault currently being carried out by Syrian regime troops to capture all areas of the country's second city.The United Nations has warned that a humanitarian catastrophe is unfolding in Aleppo unlike any witnessed so far in Syria's five-year war, which has claimed more than 300,000 lives.

Russia has said it would continue its Syrian bombing campaign in spite of US warnings that Washington would suspend talks unless Moscow stopped its assault on Aleppo.

In a phone call with US Secretary of State John Kerry on Friday, Lavrov stressed Moscow's "readiness to continue to consider additional possibilities" to work with the United States on normalising the situation in Aleppo, Russia's foreign ministry said in a statement.

Lavrov also stressed Russia "remains open for dialogue with the United States on all key issues" regarding Syria, the statement said.

The British-based Syrian Observatory for Human Rights said Friday that more than 9,300 people -- including some 3,800 civilians -- had been killed in a year of Russian air strikes in Syria in support of Assad.