U.S. President Joe Biden and his French counterpart Emmanuel Macron have promised to coordinate their response over Ukraine tensions. They spoke by phone on February 3 and affirmed their support for Ukraine's sovereignty and territorial integrity. It comes as the U.S. and its allies accuse Moscow of massing 100,000 troops on the border with eastern Ukraine, and preparing for invasion. French President Macron earlier said he might visit Russia to seek a diplomatic solution. German Chancellor Olaf Scholz also said that he would travel to Moscow to discuss the crisis on the Ukraine-Russia border.