The United Arab Emirates and Qatar on Saturday urged their citizens to avoid travel to Lebanon, where clashes linked to the conflict in neighbouring Syria have left 10 people dead.
"The UAE foreign ministry has urged citizens not to travel to Lebanon until the tense security situation there is cleared," it said in an English-language statement carried on state news agency WAM.
The advice has been issued "to guarantee the safety of its citizens," senior foreign ministry official Issa Abdullah al-Kalbani said in the statement.
Kalbani also called on "citizens currently in Lebanon to leave the country, and in case they have to stay back for any unavoidable reasons, to contact the UAE embassy in Beirut" to give their whereabouts and contact details.
Qatar issued a similar warning due to the "unstable security situation" in Lebanon, its news agency QNA reported.
Sectarian clashes in the northern Lebanese port city of Tripoli over the past week have left 10 people dead and sparked fears that the deadly revolt sweeping Syria since March 2011 could spill over into Lebanon.
Tension between the Sunni and Alawite communities in Tripoli has been fueled by the uprising and the arrival in the area of thousands of Syrian refugees fleeing the violence in their country.
Clashes broke out last weekend after the arrest of a Sunni Islamist on charges of belonging to a terrorist organisation. His supporters say he was targeted for helping Syrian refugees.
Since the outbreak of the uprising against Syrian President Bashar al-Assad in March 2011, Tripoli has become a safe haven for activists and thousands of refugees.
The Alawite sect is an offshoot of Shiite Islam to which Assad belongs and which has controlled Syrian politics for decades.