The two Nordic neighbours, which both have long borders on the Baltic Sea, applied last month to join the military alliance amid security concerns after Russia invaded Ukraine in February, although they face objections from Turkey.
Their joining would mean the Baltic Sea’s coastline would, bar short strips around Russian cities Kaliningrad and St Petersburg, be encircled by Nato members.
“So from a Russian perspective that will be very problematic for them, militarily speaking, and it would be very advantageous to Nato,” said Milley, chairman of the Joint Chiefs of Staff.
“The Baltic (Sea is) very strategically important, it’s one of the great seaways of the world,” Milley added.
He was speaking at a joint news conference with his Swedish counterpart, the Swedish prime minister and the Swedish defence minister ahead of an annual Nato exercise in the Baltic Sea that Sweden and Finland take part in.
With Sweden and Finland’s hopes to join Nato, the war in Ukraine has triggered the very kind of enlargement of the alliance on Russia’s borders that President Vladimir Putin’s invasion sought to prevent.
Putin said last month there was no threat to Russia if Sweden and Finland joined Nato, although he cautioned that Moscow would respond if the US-led alliance bolstered military infrastructure in the new Nordic members.
Swedish Prime Minister Magdalena Andersson described the US military visit as a concrete demonstration of assurances President Joe Biden gave her and Finnish President Sauli Niinisto when they went to Washington in May.
“This is a strong signal to the world. And it also shows that the security assurances that President Biden was very outspoken on … in the White House is actually also followed with concrete action,” she said.