"The issue of contributing to a mission... will be evaluated with all relevant parties if deemed necessary for the establishment of regional stability and peace," the source said.

His remarks came as European Union leaders were meeting Ukrainian President Volodymyr Zelensky in Brussels to seek ways of bolstering the defences of both Ukraine and Europe after US President Donald Trump suspended military aid to Kyiv and intelligence sharing to help it fight off Russia's invasion.

Paris and London have already expressed a willingness to deploy troops to Ukraine to ensure that a possible future ceasefire is preserved, without saying what role those troops would play.

Bolstering European defences has taken on acute urgency after Trump made clear his desire to quickly end the three-year war in Ukraine through direct negotiations with Moscow.

NATO member Turkey has sought to maintain good relations with both of its Black Sea neighbours since the Russian invasion three years ago and has twice hosted direct talks aimed at ending the war.