Washington, June 2 -- US Secretary of State Marco Rubio has spoken with his Russian counterpart about ending the Ukraine conflict, as both sides prepare for fresh negotiations in Istanbul.

The diplomatic contact between Rubio and Russian Foreign Minister Sergei Lavrov came as Ukraine and Russia conducted some of the largest drone attacks since the war began nearly three years ago.

A second round of direct peace talks is scheduled to take place in Istanbul on Monday, with Ukrainian negotiators set to present new proposals to Russian representatives.

The US State Department said Rubio had "reinforced President Trump's call for ongoing direct negotiations between Russia and Ukraine" aimed at achieving lasting peace.

During their conversa...