Syria warns it will take tough measures against any country which recognises the opposition Syrian National Council. No details were given.
Foreign Minister Walid al-Moualem said the council was not legitimate.
Formation of the SNC was announced in Turkey on 3 October to present a united common front against President Bashir al-Assad.
The BBC reports Western countries have welcomed the move, but stopped short of formally recognising it.
Mr Moualem was speaking at a joint news conference with ministers from five Latin American countries visiting Syria to show their support for the Assad government.
He also criticised Germany and Switzerland for failing to prevent Syrian missions in three cities from being attacked by protesters.
Protesters stormed Syrian diplomatic properties in Berlin and Hamburg as well as the Syrian mission in the United Nations building in Geneva on Friday.
Mr Moualem said the two countries had failed to meet their obligations to defend diplomatic missions and warned the same might happen to foreign embassies on Syrian soil.