The US will abandon its efforts “within days” to broker a peace agreement between Russia and Ukraine unless there are clear signs a settlement can be reached, the US secretary of state, Marco Rubio, has said, as Kyiv says it has signed a memorandum with the US over a controversial minerals deal.

Speaking in Paris on Friday after meeting European and Ukrainian leaders, Rubio said Donald Trump was still interested in a deal. But he added that the US president had many other priorities around the world and was willing to move on unless there were signs of progress.