The Government said it has made no decision to whether it will arm Syrian rebels, after the European Union lifted the embargo on supplying weapons to the country's opposition.
Foreign Secretary William Hague said that the decision sent a "clear message" to President Assad's regime.
However, Russia's deputy foreign minister confirmed that Moscow will provide Syria with state-of-the art air defence missiles to prevent foreign intervention in the country.
Fears are growing of an arms race in Syria after EU countries agreed they could arm rebels while Russia could give missiles to the regime.
Foreign Secretary William Hague said a "clear message" had been sent to Assad's regime after the EU decided to lift the Syrian arms embargo.