Denmark and Norway have urged their citizens to leave Syria, after the embassies of both countries in Damascus were set on fire.
Several thousand Syrian demonstrators set both embassies alight in protest at the publishing of cartoons of the Prophet Mohammad by newspapers in several European countries.
Police fired teargas to disperse the protesters.
Norwegian Foreign Minister Jonas Gahr Stoere said he had telephoned his Syrian counterpart, Faruq al-Shara and told him 'this was completely unacceptable'.
He added that Mr al-Shara 'had distanced himself from the attack, and he apologised'.
Meanwhile, Iranian President Mahmoud Ahmadinejad said his government should consider abandoning commercial and trade deals with countries where the cartoons have appeared.
Vatican appeals for mutual respect
The Vatican appealed for a climate of mutual respect in its first public comment on the controversy, saying the right to freedom of expression did not imply the right to offend religious beliefs.
However, it criticised as 'equally deplorable' the violent reaction in the Islamic world, and said that an offence committed by one person or one newspaper could not be blamed on a country or its institutions.
