France said Friday it was deploying three advanced Rafale fighter jets to Poland and the United Kingdom announced a package of new sanctions aimed at cutting revenue and supply lines to Russia, as Western governments took initial measures to signal that further aggression will not go unchecked after a Russian drone strike on Polish soil.

President Emmanuel Macron said the Rafales would help protect Polish airspace and NATO’s eastern flank, fulfilling a commitment made to Polish Prime Minister Donald Tusk. Macron said the deployment was discussed with NATO Secretary-General Jens Stoltenberg and British Prime Minister Keir Starmer and posted on X that "the security of the European continent is our top priority. We will not yield to Russia’s growing intimidation."

Britain’s sanctions target what the government described as part of Russia’s “shadow fleet” that transports oil in defiance of existing measures. The U.K. announced bans on 70 vessels and sanctions on about 30 individuals and companies, including firms based in China and Turkey, for supplying electronics, chemicals, explosives and other components used in weapons and drone systems.

British Foreign Secretary Yvette Cooper, on her first visit to Kyiv since being appointed last week, described the measures as a demonstration of solidarity with Ukraine, which has endured a large-scale assault of missiles and drones over the past year. "The U.K. will not stand idly by as Putin continues his barbaric invasion of Ukraine," Cooper said, condemning what she called Russia’s “complete disregard for sovereignty” in sending drones into NATO airspace.

The moves by Paris and London followed a Wednesday incident in which multiple Russian-launched drones struck Polish territory. European leaders called the incursions a serious breach and a deliberate provocation that raised fears Moscow’s war in Ukraine could widen beyond its borders.

Poland has stepped up bilateral cooperation with Ukraine in response. Polish Foreign Minister Radek Sikorski was visiting Kyiv and was scheduled to meet Ukrainian officials to discuss shared security concerns, Poland’s bid for EU and NATO accession, and measures to increase pressure on Moscow, according to a post by Ukraine’s deputy foreign minister Andrii Sybiha on X. Poland’s Defense Ministry said it would work with Ukraine to train personnel on anti-drone defense measures.

Polish Prime Minister Donald Tusk also dismissed public comments by former U.S. President Donald Trump suggesting the incursion might have been "a mistake," saying on X that "we would also wish that the drone attack on Poland was a mistake. But it wasn’t. And we know it." Tusk has been pressing allies for a clear and proportionate response.

Western officials framed the new actions as calibrated steps intended to increase the cost of further aggression without triggering an escalation. U.K. ministers emphasized that sanctions were designed to target revenues and supply chains Moscow depends on to sustain its war effort, while military deployments to NATO allies were presented as defensive measures to reassure partners and deter additional attacks.

Efforts led by the United States and other parties to steer Moscow and Kyiv toward a negotiated settlement have so far failed to gain traction, and the latest exchanges underscore the fragility of security in and around Ukraine. NATO allies have been reviewing defenses and contingency plans for potential spillover incidents as they weigh further political, economic and military responses.

Diplomats and defense officials said consultations among NATO members and European partners would continue in the coming days to coordinate additional measures and to evaluate the intelligence surrounding the drone strikes. Officials from France, the U.K. and Poland said any further violations of allied airspace would prompt additional steps, but provided few immediate details on what those steps might include.