Bangladesh, May 18 -- In a notable shift in diplomatic tone, US Secretary of State Marco Rubio has publicly expressed Washingtons impatience with protracted negotiations between Russia and Ukraine, urging both parties to produce concrete proposals toward ending the war. The remarks come after the first direct talks between Moscow and Kiev in three years, held in Istanbul on May 16, which resulted in a prisoner exchange deal involving 1,000 detainees on each side and a commitment to draft formal ceasefire road maps.

Rubios comments, aired during a May 18 interview on CBS News Face the Nation, reflect a mounting sense of urgency within US foreign policy circles, as global attention fractures across multiple crises and geopolitical flashpoi...