The renewed push by US President Donald Trump to negotiate an end to Russia’s war in Ukraine has injected more urgency to the latter’s bid for membership of the European Union.

Secretary of State Marco Rubio told European counterparts Thursday the US will participate in post-war security guarantees for Ukraine but that the Trump administration believes Europe should take the lead,

A source familiar with the matter said U.S. Secretary of State Marco Rubio, who also serves as Trump's national security adviser, held a conference call on Thursday with his European counterparts to discuss the options.