Russian President Vladimir Putin claimed in a call with President Trump on Monday — their second in 24 hours — that Ukraine conducted a drone attack targeting one of his official residences, a claim Kyiv immediately denied. Why it matters: Putin told Trump that Russia would revise its negotiating position based on the alleged attack, according to Moscow's readout. It's the latest indication the Kremlin is disinclined to accept the deal the U.S. and Ukraine have been negotiating for weeks...