The pair discussed the grave situation on the Ukrainian border, and agreed that the world needed to remain vigilant in the coming hours and days.
The Prime Minister thanked President von der Leyen for her close cooperation on sanctions to date, and said that the UK and the EU should continue to work with allies to prepare a package of economic measures that would punish Russia if they breached Ukraine's sovereignty.
He welcomed the unity of allies, but said more could be done to strengthen coordinated measures at pace.
The Prime Minister also raised the growing issues around the Northern Ireland Protocol, and the need to take action to safeguard the Belfast (Good Friday) Agreement in all its dimensions.
The two leaders agreed to stay in touch on both matters.
