Iran and Syria have denounced events in Venezuela, saying the opposition's claim there that it holds the presidency is a "coup" and an attempt to take over power unlawfully.
Venezuela's opposition leader Juan Guaido declared himself interim president on Wednesday, winning backing from the United States and parts of Latin America and prompting socialist Nicolas Maduro, the country's leader since 2013, to break relations with Washington.
Violence flared again on Wednesday during big protests across Venezuela, and at least seven deaths were reported in the escalating confrontation with Mr Maduro, who has been increasingly criticised by many nations. Mr Guaido said mass protests were the only way to end Mr Maduro's "dictatorship".
In Tehran, Iranian Foreign Ministry spokesman Bahram Ghasemi told reporters on Thursday that the "Islamic Republic of Iran supports the government and people of Venezuela against any sort of foreign intervention and any illegitimate and illegal action such as attempt to make a coup d'etat".
His remarks were carried by the semi-official ISNA news agency.
Mr Ghasemi also condemned what he said is an open and illegal intervention in Venezuela by the U.S. and added hopes that the Venezuelan people will overcome their political rifts and problems through peaceful and legal means.
Tehran has long been an ally of Mr Maduro.
The crisis has split the international community.
Russia on Thursday warned that US moves recognise an opposition leader as president could lead to lawlessness and bloodshed there.
The Russian Foreign Ministry said in a statement that events in Venezuela are reaching a dangerous point and it said that Washington was showing a disregard for international law.
China said that it opposed any external interference in Venezuelan politics. Beijing is Venezuela's main creditor and Mr Maduro visited the country in September, striking energy and gold mining deals as he sought China's help. The Asian giant powerhouse sent representatives to his inauguration, widely condemned as a sham, earlier this month.
Major regional players Brazil, Colombia, Chile, Peru and Argentina all gave their backing to Mr Guaido's self-proclamation as acting president.
The European Union called for free elections to restore democracy.
In Damascus, the Syrian regime condemned what it said was "flagrant intervention" by the US in Venezuela's internal affairs.
The Foreign Ministry said in a statement on Thursday that the American backing of the opposition's claim to the presidency in Venezuela constitutes a "violation of international laws and norms".
The ministry says Damascus renews its "full solidarity with the leadership and people of the Venezuelan Republic in preserving the country's sovereignty and foiling the American administration's hostile plans".
Venezuelan President Nicolas Maduro is a strong ally of Syrian President Bashar Assad.
A large Syrian community lives in Venezuela.