The Russian parliament on Wednesday unanimously granted President Vladimir Putin the right to deploy the country’s military in Syria, a move a top Kremlin aide said related only to the air force.

Russia has been building up its military presence in Syria, where it supports the government forces of President Bashar al-Assad in a conflict that pits him against Islamic State militants and Western-backed rebels.

Sergei Ivanov, the head of the Kremlin administration, said after the vote in the Federation Council, the Russian parliament’s upper chamber: “The Syrian president asked the leadership of our country for military assistance.”

But he said the vote did not mean that Russian ground forces would be engaged in conflict and that the move referred to the use of the air force only.

The last time the Russian parliament granted Putin the right to deploy troops abroad, a technical requirement under Russian law, Moscow seized Crimea from Ukraine last year.

(Reporting by Lidia Kelly, Gabriela Baczynska and Alexander Winning; Editing by Andrew Osborn)