The Biden administration is privately encouraging Ukraine's leaders to signal an openness to negotiate with Russia and drop their public refusal to engage in peace talks unless President Vladimir Putin is removed from power, according to people familiar with the discussions.The request by American officials is not aimed at pushing Ukraine to the negotiating table, these people said. Rather, they called it a calculated attempt to ensure the government in Kiev maintains the support of other nations facing constituencies wary of fueling a war for many years to come.