Russian President Vladimir Putin attends a session during the Week of Russian Business, organized by the Russian Union of Industrialists and Entrepreneurs (RSPP), in Moscow, Russia February 9, 2018. REUTERS/Sergei Karpukhin

MOSCOW (Reuters) - Russian President Vladimir Putin and U.S. President Donald Trump discussed North Korea by phone on Monday, but the discussion was not in-depth, Kremlin spokesman Dmitry Peskov said on Tuesday.

He also said that Trump offered U.S. help to Russia in investigating a fatal plane crash on Sunday which killed 71 people on board.