WASHINGTON

The US and Denmark are "standing up" for Ukraine to aid the country as it defends itself against Russia's over one-year-long assault, President Joe Biden said Monday. 

Addressing reporters in the Oval Office alongside Danish Prime Minister Mette Frederiksen, Biden said Washington and Copenhagen are working with other NATO allies to take "steps to strengthen our shared security, including finishing our bilateral defense cooperation agreement that we're working on."

"There's a shared commitment to the core values that gives us our strength. At least that's what I believe," said Biden. "Together, we're working to protect those values, including standing up for the people of Ukraine against the brutal aggression of the Russians."

Frederiksen said that because "war has returned to our continent, in Europe, it is so important that our allies and our friends -- that we stick together, that we are united."

"And we have truly been for now 15 months in Ukraine. We will, of course, continue, from a Danish perspective, our very strong -- strong support to Ukraine, but I'm looking forward to work even closer with you on defense and security," she added.

Denmark is one of several NATO allies working to train and eventually provide Kyiv with F-16 fighter jets after Biden signed off on the plan, removing obstacles to the transfer of the US-made fighter jets. The UK is also part of the effort and Prime Minister Rishi Sunak is due in Washington on Thursday.

Frederiksen did not directly refer to the planned F-16 training and transfers.