Kunis, who was born in Chernivtsi, Ukraine in 1983, moved to the United States in 1991.

"I have always considered myself an American, a proud American... But today, I have never been more proud to be a Ukrainian," Kunis said in an embedded video.

"The events that have unfolded in Ukraine are devastating. There is no place in this world for this kind of unjust attack on humanity."

Kutcher, sitting by Kunis' side in the video, said the funds would be used to provide refugee and humanitarian aid to Ukrainians affected by Russia's invasion of the neighbouring country.

"The principle challenge right now is logistics. We need to get housing and we need to get supplies and resources into the area," said Kutcher. "And I have never been more proud to be married to a Ukrainian."

The two actors, who married in 2015, have agreed to match up to $3 million of donations, with the ultimate goal of raising $30 million. They are partnering with short-term housing website Airbnb.org and Flexport.org, which organises shipments of humanitarian aid to refugees.