The United States vowed Monday to defend "every inch of NATO territory" during a UN Security Council meeting convened by Estonia after Russian aircraft entered its airspace, the third incident in ten days targeting Russia's neighbors.

"As President Trump and the United States" attempt to "end this atrocious war between Russia and Ukraine, we expect Russia to seek ways to de-escalate, not risk escalating the conflict," said the new US ambassador to the UN, Mike Waltz.

"Russia must urgently put an end to this dangerous behavior," he added.

Shortly before the emergency meeting of the Security Council, called for by Tallinn, Estonian Foreign Minister Margus Tsahkna read out a text supported by some fifty allied countries, also demanding that Moscow put an end to "provocations and threats" against its neighbors.

"Russia's irresponsible actions constitute not only a violation of international law, but also a destabilizing escalation that brings the region closer to conflict than at any time in recent years," he said.

On Friday, three Russian warplanes entered Estonian airspace and remained there for 12 minutes. Moscow denied any violation.

This incident comes just days after around twenty Russian drones flew over Polish airspace, three of which were shot down. Romania also denounced the flight of a Russian drone over the country.

"This is the third time in ten days that Russia has violated European Union and NATO airspace. This latest incursion leaves no room for doubt: Russia is choosing escalation and provocation," said Jay Dharmadhikari, France's deputy ambassador to the UN.

- "Russophobic hysteria" -

UN Under-Secretary-General for Europe Miroslav Jenca called on "all parties concerned to act responsibly, use all available channels and take immediate steps to defuse tensions and prevent further risks to regional security."

During the incident in Estonian airspace, Italian F-35 fighter jets, part of NATO's air defense support mission in the Baltic States, along with Swedish and Finnish aircraft, were scrambled to intercept the Russian aircraft.

Confronted with the evidence gathered by Estonia and its allies, the Russian deputy ambassador, Dmitry Polyanskiy, assured that "as always, there is no evidence, except for the Russophobic hysteria emanating from Tallinn."

"The Russian aircraft did not deviate from the agreed route and did not enter Estonian airspace. Their flight path took place over the neutral waters of the Baltic Sea," he stressed.

Monday's meeting at the United Nations is the first requested by Estonia in the 34 years of UN membership of the country, which is also a member of the European Union and NATO and a staunch supporter of Ukraine.

On Sunday, Donald Trump assured that the United States would participate in the defense of Poland and the Baltic countries if Russia intensified its military activity in the region.

The sometimes friendly relations between the US president and his Russian counterpart Vladimir Putin appear to have deteriorated, with the latter continuing his invasion of Ukraine despite the US leader's peace efforts.

Following an official visit to the UK on Thursday, Mr Trump said Mr Putin had "really let him down" by continuing the war, now in its fourth year.