China reiterated its opposition to unilateral sanctions against Iran, Foreign Ministry spokesman Hong Lei said on Friday, after Washington exempted China and Singapore from sanctions over purchases of oil from Iran.

US President Barack Obama is keen to persuade all countries around the world to join the US in sanctions against Iran over its nuclear program because Obama is under pressure in his re-election campaign, analysts said.

China is always opposed to one country's unilateral sanctions against another country on the basis of its domestic law. It is even less acceptable for such unilateral sanctions to be imposed on a third country.