Vice President Mike Pence said today the US intended to "deepen our relationship with the European Union and the European community".
Mr Pence, speaking at the start of his meeting with the EU's foreign policy chief Federica Mogherini in Brussels, was opening a day of meetings on the EU and Nato.
Mr Pence was facing deep scepticism among European leaders over the foreign policy direction of the new administration of President Donald Trump.
Mr Trump was supportive of the United Kingdom's vote to exit the 28-nation EU bloc last year.
He has suggested the EU could soon fall apart.
Mr Pence voiced the administration's strong support for Nato over the weekend.