Lieutenant General Vladimir ‍Alekseyev is fighting for his life after being shot several times in a Moscow apartment building - and Russia is blaming Ukraine.

The Kremlin said Thursday it regretted the expiration of the last remaining nuclear arms pact between Russia and the United States, while U.S. President Donald Trump declared he was against keeping its limits and wants a better deal.

Russian oil revenue fell 50% in January compared with the same month the previous year after tough new sanctions imposed by the U.S. Treasury.

MOSCOW, Feb 5 (Reuters) - Russia expelled a German diplomat on Thursday in response to what it said was Berlin's groundless expulsion of a Russian diplomat last month and accused Germany of being in the grip of "spy mania".

Since the collapse of the old Soviet Union, Russia has cut a substantially diminished figure on the international stage.

A Russian official said Moscow is ready to respond with military measures if the United States deploys its missile defense program to Greenland.

WASHINGTON, Feb 5 (Reuters) - The U.S. military said that Washington and Moscow on Thursday agreed to reestablish high level military-to-military dialogue, following talks in Abu Dhabi, a move which could signal a move towards normalizing some ties between the United States and Russia.

Russian President Vladimir Putin has discussed the burgeoning economic cooperation between Moscow and Beijing and their relations with the United States in a video call with Chinese leader Xi Jinping.