MOSCOW/KIEV, July 17 (Xinhua) -- Russia on Tuesday rejected U.S. President Donald Trump's 50-day ultimatum to agree to a Ukraine ceasefire, dismissing the threat of "severe tariffs" as unacceptable.

"The large-scale exchange initiated by the Russian side will continue," the ministry said. The swap followed the exchange of 270 servicemen and 120 civilians from each side announced on Friday.

WASHINGTON, July 14 (Xinhua) -- U.S. President Donald Trump said Monday that the United States will send weapons to Ukraine through NATO, and threatened "severe tariffs" targeting Russia if a ...