BRUSSELS (AP) -- U.S. Vice President Mike Pence has reassured European Union officials about the Trump administration's stance toward the bloc, European Council President Donald Tusk said Monday. 

Tusk said he and Pence held ``open and frank talks'' aimed in part at allaying concerns about President Donald Trump's support of the EU and of European security through the NATO military alliance.

"I heard words which are promising for the future, words which explain a lot about the new approach in Washington,'' Tusk said.

Tusk explained that "too many new and sometimes surprising opinions have been voiced ... for us to pretend that everything is as it used to be.''

Pence said he was looking to explore ways to ``deepen our relationship with the European Union and the European community'' as he opened a day of meetings on the EU and NATO with EU foreign policy chief Federica Mogherini in Brussels.

Pence was facing deep skepticism among European leaders over the foreign policy direction of his boss. Trump was supportive of Britain's vote last year to leave the 28-nation EU, known as Brexit. And he has suggested that the EU itself could soon fall apart.

Pence voiced the administration's strong support for NATO over the weekend.