Ukraine is desperately trying to hold off a new Russian offensive that threatens its second-largest city. U.S. officials tell the NewsHour that the administration is debating whether to lift a restriction on the use of American weapons to target Russian weapons in Russia. Nick Schifrin discussed that with former U.S. Ambassador to Ukraine William Taylor and Emma Ashford of the Stimson Center. PBS NewsHour is supported by - https://www.pbs.org/newshour/about/funders