Bolton warns Syria against using chemical weapons following US withdrawal

US National Security Advisor John Bolton has warned the Syrian government that the US withdrawal from the country should not be seen as an opportunity to use chemical weapons against opposition rebels 

Last month, President Donald Trump said US troops had succeeded in their mission to defeat Islamic State (IS) and were no longer needed in Syria.

"There is absolutely no change in the US position against the use of chemical weapons by the Syrian regime and absolutely no change in our position that any use of chemical weapons would be met by a very strong response, as we've done twice before," Bolton told reporters on his plane shortly before landing in Tel Aviv, Israel.

"So the regime, the Assad regime, should be under no illusions on that question," said Bolton, who is on a four-day trip to Israel and Turkey.

Trump's announcement, which took officials in Washington and allies abroad by surprise, contributed to Jim Mattis' decision to resign as US defence secretary and prompted concern that IS could stage a comeback.

Bolton's remarks come after a US State Department official said on Friday that there was no official timeline for the US withdrawal from Syria.

'A lot of options would be on the table'

Trump has twice bombed Syria over the government’s alleged use of chemical weapons, in April 2017 and April 2018, the Reuters news agency reported.

In September, a senior US official said there was evidence that the Syrian government was preparing to use chemical weapons in Idlib, the last major rebel stronghold in the country.

More than half a million people have died during the Syrian war, and 11 million have been forced to flee their homes.

During his trip, Bolton is set to meet with Israeli Prime Minister Benjamin Netanyahu and Turkish President Recep Tayyip Erdogan. He said he was not suggesting Syria appeared ready to use chemical weapons.

"As we elaborate how the [US troop] withdrawal is going to occur and the circumstances, we don't want the Assad regime to see what we do as representing any diminution in our opposition to the use of weapons of mass destruction," he said.

If chemical weapons were to be used, "a lot of options would be on the table ... if they don't heed the lessons of those two strikes the next one will be more telling," Bolton said.