President Volodymyr Zelenskiy said on Monday that Ukraine had to engage in "substantive" diplomacy to bring to a rapid end the three-year-old war with Russia, and he hoped to be able to rely on U.S. support in securing peace.

President Donald Trump’s senior aides and allies lashed out at Ukrainian leader Volodymyr Zelenskyy from Washington as he attended a European summit in London to rally international support for his mi