BRUSSELS — NATO allies are putting forces on standby and sending additional ships and fighter jets to eastern Europe, the organization said Monday. The development comes after weeks of rising tensions, as a build-up of Russian troops near the border with Ukraine prompts fears that Moscow may be planning to launch an invasion. Wadi Rum fly over... Copy video url Play / Pause Mute / Unmute Report a problem Language Mox Player "NATO will continue to take all necessary measures to protect and defend all Allies, including by reinforcing the eastern part of the Alliance," NATO Secretary General Jens Stoltenberg said in a statement Monday, welcoming the allies" extra contributions to the military alliance. "We will always respond to any deterioration of our security environment, including through strengthening our collective defence," he added. The Kremlin denies it is planning to attack Ukraine, and argues that NATO support for the country constitutes a growing threat on Russia"s western flank. Latvia"s Foreign Affairs minister Edgars Rinkēvič has called on NATO to address the "continuous" Russian and Belarusian military build-up on Ukraine"s borders, with "appropriate" countermeasures. Rinkēvičs tweeted Monday: "We are reaching the point where continuous Russian and Belarusian military buildup in Europe needs to be addressed by appropriate NATO countermeasures." "It is time to increase allied forces presence in the Alliance"s Eastern flank both as measures of defense and deterrence," the minister added. US President Joe Biden discussed options for bolstering US troop levels in the Baltics and Eastern Europe with his top military officials during a briefing at Camp David on Saturday, according to a senior official. On Sunday, the US State Department announced that it would reduce staff levels at the US Embassy in Kyiv, Ukraine, out of an "abundance of caution," beginning with the departure of nonessential staff and family members. Speaking to reporters on his way into the EU Foreign Affairs Council in Brussels on Monday, the bloc"s chief diplomat Josep Borrell said no decision had been made on ordering European Union diplomatic staff and their families to leave Ukraine. "We are not going to do the same thing, because we don"t know any specific reasons," said Borrell. The UK Foreign Office also announced Monday that some British Embassy staff and dependents are being withdrawn from Kyiv in response to growing threats from Russia. Representatives from the four countries involved in the "Normandy Format" talks -- France, Germany, Russia and Ukraine -- will meet on Wednesday to discuss the situation in Ukraine, an Élysée spokesperson confirmed to CNN. — CNN