BRUSSELS (AP) — NATO announced Tuesday that the alliance will hold a virtual meeting of foreign ministers from the 30 member nations this week to assess the situation in Ukraine and upcoming talks with Russia.

The extraordinary meeting of the alliance members on Friday will kick off a week of intense diplomacy over the military buildup on Ukraine's borders and initiatives to ease the tension between the Cold War foes.

U.S. President Joe Biden has warned Russian President Vladimir Putin that Washington could impose new sanctions against Moscow if it takes further military action against Ukraine. Putin responded that such a U.S. move could lead to a complete rupture of ties between the nations.

The two leaders spoke frankly for nearly an hour last week amid growing alarm over Russia's troop buildup near Ukraine, a crisis that has deepened as the Kremlin has stiffened its insistence on border security guarantees and test-fired hypersonic missiles to underscore its demands.

Putin and Biden have spoken twice over the past month, before scheduled talks between senior U.S. and Russian officials on Jan. 9 and 10 in Geneva. Those talks will be followed by a meeting of the Russia-NATO Council on Jan. 12 and negotiations at the Organization for Security and Cooperation in Europe in Vienna on Jan. 13.