Polish President Andrzej Duda on Monday said NATO members should increase their defence spending to three percent of GDP in response to Russia's aggression against Ukraine.
The Western defence alliance currently has a defence spending target of 2 percent of gross domestic product, though Poland already spends around 4 percent.
"I want to propose in the near future... that NATO members decide together that the alliance requirement will be to spend not 2 percent, but 3 percent of GDP on defence," Duda told reporters.
"That will be the threshold below which it will absolutely not be recommended to go," he added ahead of visits to Washington and Brussels.
On Tuesday, Duda and Polish Prime Minister Donald Tusk will meet with U.S. President Joe Biden to mark 25 years since Poland, the Czech Republic and Hungary joined NATO.
Duda said NATO must give a "clear and courageous response to Russian aggression".
"This response will consist of increasing the military capacity of the North Atlantic Alliance," he added.
NATO is a "defence alliance, and defence means that if someone threatens us, we react."
In a separate video address to the nation, Duda called his proposal "the best response to today's threats to international security".
He also penned an opinion piece on the topic that was published by the Washington Post on Monday.
