Russia has revoked the accreditation of six British diplomats, accusing them of espionage as tensions rise ahead of a critical meeting between U.S. President Joe Biden and UK Prime Minister Keir Starmer. President Vladimir Putin warned that if Ukraine is allowed to use Western long-range missiles, it would signify direct NATO involvement in the conflict, escalating hostilities. He asserted that this would change the nature of the war, implying that Russia would respond with appropriate measures if such weapons were deployed. The UK has been under pressure to supply Ukraine with long-range missiles, despite concerns over provoking Moscow. The Russian Federal Security Service (FSB) claims the British diplomats were coordinating efforts to escalate military tensions against Russia. As both sides brace for potential shifts in strategy, the broader implications of NATO's involvement remain a contentious issue.