Serbian President Boris Tadic criticized a Russian ambassador on Tuesday for addressing an opposition nationalist gathering, but indicated he won't be expelled.
Several liberal groups in Serbia have demanded that Russian Ambassador Aelksandr Konuzin be declared persona non grata after he spoke at an anniversary meeting of the opposition nationalist Serbian Progressive Party on Saturday.
Serbian media quoted Konuzin as saying the party "has become a true reflection of the popular mood" in Serbia.
Tadic said diplomats often attend party meetings, but "it is not a common practice for diplomats to speak" at them.
The president said he wants his statement to end a debate between Serbian liberals and nationalists about whether Konuzin should be expelled from Serbia.
Tadic heads the pro-Western Democratic Party which will face a tough challenge from the nationalists and former allies of Serbia's late strongman Slobodan Milosevic in elections next year.
Konuzin has clashed in the past with Serbian liberals, who have accused him of non-diplomatic behavior.
He recently stormed out of a security forum in Belgrade, accusing its participants of not doing enough to defend Serbia's claim to the breakaway province of Kosovo, which declared independence in 2008. Russia is Serbia's traditional Orthodox Christian ally and has backed the country in its opposition to Kosovo independence.
Serbia's nationalists have advocated strong ties with Russia and the abolition of Serbia's bid to join the European Union because of Western support for Kosovo's statehood.