Russia President Vladimir Putin claimed Crimea as a Russian territory and NATO countries that border Russia are concerned over Putin’s next move. Britain offered to supply their NATO allies with six Typhoon jets.

British Defence Secretary Philip Hammond will send six RAF jets to the three Baltic nations, Estonia, Lithuania and Latvia, who joined NATO in 2004.

“I hope that will provide reassurance to our NATO allies,” Philip Hammond said Monday, as reported by ITV news.

The U.K. will send its Eurofighter Typhoon jets to the region in late April. According to newspaper Lithuania Tribune, the six jets will be added to the scheduled rotation by the Polish air force.

Vice President Joe Biden is in Poland and said the US is also committed to the security of their NATO allies. Last week, the US sent 300 air troops and a dozen F-16 fighters to Poland. He will also meet with the leaders of the Baltic nations. The Baltic states are small and considered vulnerable. Lithuania and Poland asked for NATO consultations during the protests in Kyiv under Article 4.

After continued Russian military threats to Crimea and Ukraine, Lithuania and Poland requested a NATO consultation to discuss Russia’s stance, according to Article 4 in the alliance’s charter, which stipulates that “the Parties will consult together whenever, in the opinion of any of them, the territorial integrity, political independence or security of any of the Parties is threatened.”

Another concern is Belarus, an ex-Soviet Union state, which borders Latvia, Lithuania and Poland. The country is still a Russian ally and Russia said they will move more military forces to Belarus.

Also Monday, Russia’s Air Force Commander Lieutenant General Viktor Bondarev, said 24 Russian Su-27s will be deployed in Belarus by the end of 2014.

“Right now in Belarus we have four Su-27SM3 jets that carry out tasks of the Union State of Russia and Belarus air force,” Bondarev said, as reported by Russian online news daily Itar-Tass News Agency. “According to the plan for this year, we add a squadron there, and by the year end at the Baranovichi aerodrome, where our air base is, we shall have a regiment of Su-27SM3 of two squadrons — the total of 24 fighters,” he said.

The US and European Union placed sanctions against Russia and added more on Monday after Crimea voted to leave Ukraine to join Russia. However, Russia pushed them aside with one official laughing at President Obama on Twitter. The Daily Beast reported Russia will impose sanctions on US politicians and Obama officials.