By Nandita Bose and Luiza Ilie BUCHAREST (Reuters) – President Vladimir Putin shows no sign of being willing to engage in diplomacy, U.S. Vice President Kamala Harris said on Friday during a visit to Romania three weeks into Russia’s invasion of Ukraine. Harris credited Romania for taking in thousands of people fleeing the fighting in neighbouring Ukraine and said Washington was constantly reassessing support levels for its NATO allies according to the dynamic situation on the ground. “From everything that we know and have witnessed, Putin shows no sign of engaging in serious diplomacy,” Harri…