A look at where Russia has gained momentum on the battlefield, but how it could struggle to sustain it.

U.S. Secretary of State Marco Rubio and Russian Foreign Minister Sergei Lavrov are meeting in Riyadh for high-stakes talks that could shape the end of the war in Ukraine and remake ties between Moscow and Washignton.

Vice President JD Vance told The Wall Street Journal that it was too early to talk about specific territorial or security arrangements.