Iranian Foreign Minister Mohammad Zarif warned Saudi Arabia on Tuesday not to deploy troops in Syria, saying it would violate international law, while also demanding that Riyadh stop bombardments in Yemen, AFP reports.

Zarif, whose country supports the regime of Syrian President Bashar al-Assad, was questioned about Saudi Arabia's announcement that it could deploy ground forces as part of the US-led coalition fighting the "Islamic State" (ISIS) terrorist group.

"Those who are operating in Syria without the authority of the sovereign government in Syria are violating international law," he told a news conference at the European Parliament in Brussels.