UNITED NATIONS, Sept. 4 (Xinhua) -- The UN Security Council will discuss the situation in Idlib, the last major rebel stronghold in Syria, on Friday, said U.S. ambassador to the United Nations Nikki Haley.

Haley, whose country is taking over the presidency of the Security Council for September, on Tuesday warned against the use of chemical weapons in Idlib, saying U.S. President Donald Trump has made it clear that the country will respond if chemical weapons are used.

"This is a tragic situation, and if they want to continue to go the route of taking over Syria, they can do that. But they cannot do it with chemical weapons. They can't do it assaulting their people and we're not going to fall for it," Haley told reporters when presenting the Security Council's program of work for September.

She said a Security Council meeting has been scheduled for Friday morning so that the council will be acting before a chemical weapons attack would take place.

"What you are seeing is the Security Council come together and say: we will not kind of sit by and wait until after the chemical weapons attack. We want to have a meeting now to discuss what should not happen," said Haley.

The United States and its Western allies were threatening Syria with the use of force over allegations that the Syrian government is planning a chemical attack in Idlib province, the last major rebel stronghold in the Arab country.

Damascus read the threats as the Western powers' way to hinder the government forces' planned assault in Idlib under false pretexts of chemical weapons' use.