The Syrian army's capture of Aleppo — which has come under renewed bombardment in an effort to seize its rebel-held sector — would be "a very important springboard" to pushing "terrorists" back to Turkey, President Bashar al-Assad has said.

Key points: Syrian President Assad says he must keep "cleaning" Aleppo

Syrian President Assad says he must keep "cleaning" Aleppo US, Russia are to resume Syria talks today

US, Russia are to resume Syria talks today Mr Assad likens Syrian proxy wars to Cold War

Rescue workers said Syria's military backed by Russian warplanes had killed more than 150 people in eastern Aleppo this week, in support of its offensive against the city.

Rising casualties in Aleppo, where many buildings have been reduced to rubble or are lacking roofs or walls, have prompted an international outcry and a renewed diplomatic push, with talks between the United States and Russia planned for Saturday.

"You have to keep cleaning this area and to push the terrorists to Turkey, to go back to where they come from, or to kill them. There's no other option," Mr Assad said in an interview.

"Aleppo is going to be a very important springboard to do this move."

As the air strikes and shelling of the city's east intensified after a brief period of relative calm, Syria's Government approved a United Nations plan to allow aid convoys into the most besieged areas of Syria, with the exception of Aleppo.

Syria's civil war, now in its sixth year, has killed 300,000 people and left millions homeless while dragging in regional and global powers as well as inspiring jihadist attacks abroad.

'The West never ended the Cold War': Assad

Mr Assad is backed by the Russian air force, Iran's Revolutionary Guards and an array of Shiite militias from Arab neighbours, while Sunni rebels seeking to oust him are backed by Turkey, the United States and Gulf monarchies.

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Mr Assad also told the newspaper that the country's civil war had become a conflict between Russia and the West.

"What we've been seeing recently during the last few weeks, and maybe few months, is something like more than Cold War," Mr Assad said.

"I don't know what to call it, but it's not something that has existed recently, because I don't think that the West and especially the United States has stopped their Cold War, even after the collapse of the Soviet Union."

Mr Assad added that Turkey's actions in Syria constituted an "invasion, against international law, against the morals, against the sovereignty of Syria".

US Secretary of State John Kerry and Russian Foreign Minister Sergei Lavrov are due to meet in Switzerland on Saturday to resume their effort to find a diplomatic solution along with counterparts from some Middle Eastern countries.

Reuters