Washington - The United States cautiously welcomed Syria's formal establishment of diplomatic relations with Lebanon on Tuesday.

US State Department spokesman Sean McCormack said the two neighbouring countries still must define final borders. He also cautioned that "behavior beyond just setting up these embassies and establishing diplomatic relations also matters."

Syrian President Bashar al-Assad issued an order Tuesday cementing diplomatic ties and announcing plans to set up an embassy in Beirut and exchange ambassadors.

Syria has not had formal diplomatic relations with Lebanon since both countries gained independence from France more than 60 years ago.

Syria's 30-year occupation of Lebanon ended in 2005 after US-led international pressure on Damascus forced the withdrawal of troops a few months after the assassination of former Lebanese prime minister Rafik Hariri.

Syria has been implicated in the assassination of Hariri and other prominent figures in Lebanon opposed to Syrian meddling in the country. (dpa)