Assad and Sudani discussed securing their shared 600km border from security threats, including Islamic State (ISIS) militants, and agreed to enhance cooperation to reduce drug smuggling, they said during a joint news conference.

Sudani said they also discussed ways to combat drought conditions in both countries caused by a reduction in rainfall, climate change and upstream damming by Turkey.

"We need to cooperate to get our fair share of water," Sudani said.

Sudani said Iraq supported the lifting of sanctions on Syria, put in place and expanded by the U.S. and European countries since 2011.

Iraq and Syria have maintained relations throughout Syria's civil war even as other Arab states withdrew their ambassadors and closed their embassies in Syria.

Baghdad and Damascus also cooperated in the fight against ISIS, whose territorial control once spread from Iraq into Syria till it suffered a defeat in the hands of the Kurdish-led Syrian Democratic Forces (SDF) and the US-led international coalition.

Sudani's visit comes as other countries, including Saudi Arabia, rebuild relations with Damascus after years of tensions.

Syria was suspended from the Arab League in 2011 in the wake of the civil war in the country. Anti-protests that year quickly turned into an armed conflict between government forces and some Islamist factions, who were provided support by countries including the US, Turkey and several regional states.

After regaining control of large parts of Syria with military and economic support from Russia and Iran, Syria was readmitted to the Arab League in May, and countries in the region are now seeking dialogue with Damascus.