WASHINGTON, Nov. 28 -- The U.S top diplomat pledged on Tuesday to strengthen ties with Europe amid mounting disputes that seem to drift the traditional allies apart.

The United States places "highest importance" on security relationships with Europe, including NATO, said U.S. State Secretary Rex Tillerson in a speech delivered at a think tank in Washington.

Tillerson's remarks came ahead of his Europe tour next week, which was seen as a chance to forge ahead the transatlantic relations which had been at risk of going sour, since U.S. President Donald Trump took office.