Sullivan: ‘We will not tolerate any aggression’ toward Sweden, Finland during NATO process

National security adviser Jake Sullivan on Wednesday warned the U.S. would “not tolerate any aggression” toward Sweden and Finland as the Nordic countries prepare to join the security alliance NATO.

During a White House press briefing Wednesday, Sullivan said Article 5, which rules an attack against one NATO nation is an attack against all, would not apply to Finland and Sweden until the countries were ratified by all 30 members.

But Sullivan said the U.S. and NATO allies were “prepared to send a very clear message” to any potential aggressors, such as Russia, during the application process.

“We will not tolerate any aggression toward Finland or Sweden,” Sullivan said. “And there are practical measures that we can take along those lines.”

Russia last week signaled it might have to take “retaliatory steps” against Finland and Sweden if they joined the security block. Russia invaded Ukraine in late February in part because of Kyiv’s increasing desire to potentially join the military alliance.

U.S. experts have determined Russia is likely to launch, at the very least, small cyberattacks against Finland and Sweden following their NATO applications.

Sullivan said the U.S. “stands ready” to ensure defense capabilities for Finland and Sweden if needed, although he noted they do not get security from NATO’s Article 5 until they are ratified.

On Sunday, Finnish President Sauli Niinistö said Russian President Vladimir Putin took the news of his country joining NATO “calmly,” despite the rhetoric from last week.

“Altogether the discussion was very, would I say, calm and cool,” the Finnish leader said. “He didn’t repeat those threats he had earlier.”

Some hurdles to Finland’s and Sweden’s NATO applications remain, including resolving objections from Turkey over what they say is the harboring of terrorists in the Nordic nations.

President Biden will be meeting with Niinistö and Sweden’s prime minister at the White House on Thursday to discuss the application.

Sullivan on Wednesday said he was confident that Turkey’s concerns would be addressed. He added the U.S. fully supports Finland and Sweden, calling them “highly capable security partners.”

“We believe that Russian aggression has only reinforced the argument for the kind of defensive alliance that NATO presents,” he said.