WASHINGTON (Reuters) -Ukraine has little chance of surviving Russia's assault without U.S. support, President Volodymyr Zelenskiy said on Friday after phone calls this week by U.S. President Donald Trump with Zelenskiy and Russian President Vladimir Putin."Probably it will be very, very, very difficult. And of course, in all the difficult situations, you have a chance. But we will have low chance - low chance to survive without support of the United States," Zelenskiy said in an interview on the NBC News program "Meet the Press."An excerpt was released on Friday from the interview, which will be broadcast on Sunday.Trump discussed...