Syrian President Bashar Al-Assad begins on Thursday his first official trip to China in almost two decades, where he will ask a longtime ally for financial support to help rebuild his devastated country.

China will become one of only a handful of countries outside the Middle East that Assad has visited since the 2011 start of a war that has since killed more than half a million people, displaced millions more, and battered Syria's infrastructure and industry.

Assad also becomes the latest in a string of leaders ostracised by the West to be feted by Beijing, with Venezuelan leader Nicolas Maduro, Iran's President Ebrahim Raisi, as well as top Russian officials, all visiting this year.

On Saturday, Assad will attend the opening ceremony of the Asian Games in the eastern city of Hangzhou. He and other foreign leaders will meet there with Xi, Chinese state broadcaster CCTV said.

According to the Syrian presidency, he will also visit Beijing.

The visit will be Assad's first to China since 2004.

Beijing has long provided Damascus with diplomatic support, particularly at the UN Security Council where it is a permanent member.

Officials from both countries have also made visits over the years.

"This visit represents an important rupture in the diplomatic isolation and the political siege imposed on Syria," Damascus-based political scientist Oussama Dannoura told AFP.

"China has been breaking Western taboos that seek to prevent a number of states from dealing with countries that Washington considers isolated," he added.

Growing presence

The visit comes as China expands its engagement in the Middle East.

Earlier this year Beijing brokered a deal that saw longtime regional rivals Saudi Arabia and Damascus backer Iran agree to restore ties and reopen their respective embassies.