Germany has scrambled two fighter jets to intercept Russian military planes above the Baltic Sea.
The German air force tracked the Russian IL-20 military aircraft as it entered neutral airspace.
"Once again, our quick reaction alert force, consisting of two Eurofighters, was tasked by Nato with investigating an unidentified aircraft without a flight plan or radio contact in international airspace," Germany's air force said in a statement.
"It was a Russian IL-20M reconnaissance aircraft. After visual identification, we handed over escort duties for the aircraft to our Swedish Nato partners and returned to Rostock-Laage."
Tensions between Nato and Russia have risen in the past few years, following deliberate, provocative acts by the Kremlin.
On Friday, three Russian MiG-31 fighters violated Estonian airspace, but Moscow denies this.
Donald Trump said the US "would" defend EU countries from Russian aggression, saying he "did not like" Russia's recent acts.
Estonia condemned the "brazen" behaviour by Russia, with Nato's North Atlantic Council set to meet on Tuesday to discuss the violation.
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Estonia's Foreign Minister Margus Tsahkna said the violation was 'part of a broader pattern of escalation by Russia'
|REUTERS
Estonian foreign minister, Margus Tsahkna, said the move was "part of a broader pattern of escalation by Russia, both regionally and globally".
Mr Tsahnka added: "This behaviour requires an international response."
Estonia's defence minister, Hanno Pevkur, said Russia's actions were aimed at diverting the West's focus away from Ukraine.
He said: "This is exactly what Russia wants - to divert our attention away from helping Ukraine and to focus on our own backyard. That's the key goal."
Latvia's President, Edgars Rinkevics, warned that a "serious conflict" could escalate if Russia continues its provocations of Nato.
He said: "Russia is doing just enough to make it seem like it is not going too far. But, knowing both the logic of thinking in Russia and the frequent incompetence at various levels, this [a conflict] could happen. The responsibility will lie with the Kremlin."
Royal Air Force fighter jets flew into Polish airspace last week, as the UK sent a "clear signal to Vladimir Putin".
The two RAF Typhoons took off from a British military base in eastern England on Friday night to patrol Polish skies and deter and defend against aerial threats from Russia, including drones.
John Healey condemned the recent violations by Russia
| REUTERSThe Government has promised to commit 2.6 per cent of GDP to boost defence spending by April 2027, in a signal to US President Donald Trump that the UK can help grow Europe's security.
Defence Secretary John Healey condemned the recent violation of Estonian airspace by Russia.
He said it was one of the "latest reckless and dangerous acts [in] the third violation of Nato airspace in recent days".
President of the European Commission, Ursula von der Leyen, echoed Mr Healey thoughts, saying: "Europe stands with Estonia in the face of Russia's latest violation of our airspace. We will respond to every provocation with determination while investing in a stronger eastern flank."