Iraqi Prime Minister Mohammed Shia Al-Sudani held talks with Syrian President Bashar al-Assad in Damascus on Sunday in the first such visit by an Iraqi premier since the outbreak of the Syrian war in 2011.
Assad and Sudani discussed securing their shared 600-kilometer border from security threats, including Islamic State 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 United States and European countries since 2011.
Iraq and Syria, which have close economic, military and political ties to regional heavyweight Iran, maintained relations throughout Syria's civil war even as other Arab states withdrew their ambassadors and closed their embassies in Syria.
Baghdad and Damascus, along with Shi'ite armed groups backed by Iran, cooperated in the fight against Islamic State, which spread from Iraq into Syria and at one point controlled more than a third of both countries.
Farhad Alaaldin, foreign affairs adviser to the prime minister, said before the meeting that Sudani was set to discuss combatting the flow of the amphetamine Captagon and possibilities for reopening a Mediterranean oil export pipeline, which could help Iraq diversify its export routes.
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 over Assad's brutal crackdown on protests and several Gulf states supported the armed opposition to his rule.
But Assad has regained control of most of Syria with military and economic support from Russia and Iran, Syria was readmitted to the Arab League in May, and regional countries are seeking dialogue with him to end drug smuggling and return millions of refugees.
Syria has agreed to help end drug trafficking across its borders with Jordan and Iraq.
Top Syrian officials and relatives of Assad have been put on sanctions lists in recent months in the United States, United Kingdom and European Union over their alleged ties to the trade.
The Syrian government denies involvement in the drug trade.