BRUSSELS, Dec 17 — EU leaders issued a joint warning to Russia on Thursday that it will face "massive consequences” if it invades Ukraine, which would include measures coordinated with allies.

The leaders adopted a declaration saying that Moscow must "de-escalate tensions caused by the military build-up” it has ordered along the border with Ukraine and urged it to engage in diplomatic talks through an existing forum with Paris, Berlin and Kiev.

An invasion would bring a "severe cost in response, including restrictive measures coordinated with partners”, the summit conclusions said, amid reports that the US was urging the Europeans to prepare a joint riposte against Moscow.

The warning came as Western allies have roundly rejected Russia’s attempt to thwart Ukraine’s Nato ambitions and efforts by Russia’s President Vladimir Putin to deal with the US directly to resolve the crisis. — AFP