In addition to the already existing commitments taken on at the NATO summit in Warsaw, the US is ready to deploy 4,200 troops in Eastern Europe, including the Baltic States, US Vice President Joe Biden said in Riga on Tuesday.

The vice president explained that in the Baltic States, the US soldiers would take part in dozens of military training exercises. This would be a mechanized brigade complete with military equipment and vehicles.

"America will never fail to defend our allies," said Biden. "We will respond. With Russia once more taking aggressive actions and threatening the sovereign rights of its neighbors, NATO remains as vital today as it ever has been. Aggression still happens in Europe and we must all be ready to answer to that aggression. An attack on one is an attack on all. Period. End of sentence. It's that basic — it's that simple. And we want you to know — we want Moscow to know that we mean what we say."

The US Vice President noted that Washington was already actively cooperating with the Baltic States to improve their weaponry. Estonia, for instance, has already purchased Javelin anti-tank missiles, and the Latvian armed forces are learning to use US Sentinel radio locators.

At the same time, NATO has never been a one-way street, added the vice president, pointing out that NATO is strong when Europe is secure and stable.

"The friendship between the Baltic States and the US is everlasting," Biden continued, adding that the US considers Article 5 of the NATO Treaty its "sacred obligation." He repeatedly called on the Baltics to ignore Republican presidential candidate Donald Trump's rhetoric, as "he knows not of what he speaks."

In an interview published in the New York Times in July, Donald Trump, the Republican candidate for US president, called Article 5 of the NATO treaty into question by warning that under him as president, the US would come to the aid of the Baltic countries in the event of a Russian invasion only if he was satisfied that they had "fulfilled their obligations to us."