"I have of course been informed of the letter from the Russian Ministry of Defence and the proposal it contained," Rõivas said at the government's press conference.

In his words, security and safety over the Baltic Sea are issues about which Estonia has been talking for years. "And if Russia's wish to increase safety is sincere, I have a simple recommendation: find the aircraft's transponder button and switch it on," he said.

According to Rõivas, Estonia is not going to discuss defense cooperation separately with Russia because it discusses these themes jointly with allies. Furthermore, there can be no talk about defense cooperation with Russia as long as Russia's aggression in Ukraine continues. When it comes to Russia, return to normal relations will not be possible until Russia has taken steps to let Ukraine live in peace, he added.

The Russian Ministry of Defence said on Monday that Moscow was ready to take steps to boost safety of military flights above the Baltic Sea. The Russian ministry has invited experts from the Baltic States and NATO to Moscow for consultations to work out measures to implement Finnish President Sauli Niinistö's initiative, Russia's Deputy Defence Minister Anatoly Antonov told reporters.

According to the minister, the Russian Ministry of Defence is prepared to "ensure military aviation flights over the Baltic only with transponders on" on the basis of mutuality.

Antonov also said that Russia is ready "for the joint work of precluding incidents at sea and in the air under bilateral agreements in this sphere, as well as for consultations with the defense ministries of Latvia, Lithuania, Estonia, Poland, Sweden and Finland to address mutual concerns over military activity in border areas."

According to Estonian MEP Urmas Paet, however, Russian military jets have continued conducting flights over the Baltic Sea with their transponders off, pointing out that hundreds of such flights have occurred this year alone, and that they pose a significant threat to civil aviation flights taking off, landing and flying within the same airsplace. "In such a situation, aircraft with their transponders turned off are dangerous."

Paet noted that this danger to civilian flights in the Baltic Sea region would continue for so long as military aircraft continued conducting flights in the region with their transponders turned off. "Therefore this situation needs to be handled between countries and the situation must change quickly," said the MEP. "Perhaps this time something will change before an accident occurs."