The threats, pressure and ultimatums have come and gone, but Russian President Vladimir Putin has maintained Moscow’s uncompromising demands in Ukraine, raising fears he could use a planned summit with U.

For President Vladimir V. Putin of Russia, it is an opportunity not just to end the Ukraine war on his terms but to split apart the Western security alliance.

The talks in the UK came just a day after Trump announced the face-to-face meeting with Putin set for Aug. 15 in Alaska to continue negotiations to end the war that has dragged on for more than three years.