US secretary of defence Lloyd Austin welcomed the prime minister of Ukraine, Denys Shmyhal, to the Pentagon on Wednesday, 12 April.
Mr Shymal's visit comes after highly classified military and intelligence documents containing sensitive information on topics including Ukraine’s defence were leaked online.
US officials have since launched a multi-agency investigation into the leak.
Documents included information relating to the war in Ukraine, China, the Middle East, and Africa, with many officials suspecting that they may have been leaked by an American, rather than an ally.
Officials have not ruled out the possibility that pro-Russian elements could be behind the leak.
The leak is seen as one of the most serious security breaches since more than 700,000 documents, videos, and diplomatic cables appeared on WikiLeaks in 2013.
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