U.S. Ambassador to the United Nations, Linda Thomas-Greenfield holds a news conference to mark the start of the U.S. presidency of the U.N. Security Council for March, at U.N. headquarters in New York, U.S., March 1, 2021.
U.S. Ambassador to the United Nations, Linda Thomas-Greenfield holds a news conference to mark the start of the U.S. presidency of the U.N. Security Council for March, at U.N. headquarters in New York, U.S., March 1, 2021. Reuters / Mike Segar

Washington's U.N. envoy visited southern Turkey on Wednesday to assess aid deliveries across the border into Syria as the Biden administration gears up for a likely showdown with Russia at the U.N. Security Council over the operation's renewal.

The council mandate for the long-running humanitarian operation, which Russia and China have already reduced to just one Turkish border point into a rebel-held area in Syria, is due to expire on July 10.

When the 15-member council first authorised cross-border aid deliveries into Syria in 2014, supplies were allowed to pass through four border points from Turkey, Iraq and Jordan.

U.S. Ambassador to the United Nations Linda Thomas-Greenfield said the main aim of her trip was "to get updated on the situation on the ground so we're in a position, a better position, to negotiate for the extension".

She said she wanted the Syrian people to know that after 10 years of war they had not been forgotten.

She met members of the opposition-run Syrian civil defence service known as the White Helmets on Wednesday and was also due to meet Syrian refugees, U.N. and Turkish officials and aid workers.

U.N. Secretary-General Antonio Guterres has appealed to the council to again renew the operation's mandate, saying doing so was a "moral and humanitarian imperative". The United Nations says the aid shipments help more than 4 million people.

Russia and the United States reached a last-minute deal in 2021 to renew the sole remaining Turkish aid crossing after U.S. President Joe Biden raised the issue with Russian President Vladimir Putin.

Tensions between Washington and Moscow were fraught at that time, but have worsened since Russia's Feb. 24 invasion of Ukraine.

Russia has signaled its opposition to renewing the aid operation, arguing that it violates Syria's sovereignty and territorial integrity, and that more humanitarian help should be delivered from within Syria.

After meeting Thomas-Greenfield, White Helmets member Ammar Alselmo said having to rely on humanitarian help delivered from inside Syria would be "catastrophic".

A Security Council resolution needs nine votes in favour and no veto by Russia, China, the United States, France and Britain to pass.