Russia: Syria ground troops 'will lead to world war'

The use of ground troops in the Syrian conflict may lead to a world war, Russia Prime Minister Dmitry Medvedev said in an interview published on Thursday.

The US welcomed a Saudi offer to deploy special forces to support a coalition ground operation against the Islamic State group [IS] in Syria.

But Medvedev warned the move could lead to all-out war.

"A ground operation draws everyone taking part in it into a war," he was quoted saying in an interview published on Thursday by the German newspaper Handelsblatt.

"This is bad, as a ground offensive usually turns the war into a permanent one. Just look at what happened in Afghanistan and many other countries," the prime minister added.

"The Americans and our Arab partners must consider whether or not they want a permanent war," Medvedev urged.

The Russian prime minister also criticised Western powers' alleged refusal to cooperate with Moscow after the Russian defence ministry accused the US-led coalition of refusing to share intelligence on IS targets in Syria.

Meanwhile, US Defence Secretary Ash Carter welcomed Saudi Arabia's commitment to expand its role in airstrikes against IS militants in Syria.

During a meeting at the NATO headquarters in Brussels, defence ministers from more than two dozen countries gave a "broad endorsement" to a refined US plan for defeating the militants, Carter said.

"I am very pleased that so many nations have stepped up and answered the call, even in recent days," he added.

"This ministerial marks the beginning of a new stage in the coalition campaign to defeat [IS]," Carter said.

Countries not answering his call to do more may regret their choice when the struggle is over, the US defence secretary warned.

"We will all look back after victory and remember who participated in the fight," Carter said.