"The (Biden) administration is coming around the idea of Stoltenberg staying on for another year," said the U.S. official, who also spoke on condition of anonymity.
But, as some governments push for a first female NATO secretary-general, Danish Prime Minister Mette Frederiksen is also emerging as a serious contender.
Frederiksen met U.S. President Joe Biden in Washington earlier this month, before Stoltenberg visited the White House this week for talks with Biden.
Biden believes Stoltenberg has done a tremendous job during a challenging time, a view held by many other allies, the source added.
Reporting by Humeyra Pamuk and Steve Holland; writign by Simon Lewis; editing by Jonathan OatisOur Standards: The Thomson Reuters Trust Principles.
Persons:
Jens Stoltenberg, Stoltenberg, Biden, Ben Wallace, Mette Frederiksen, Frederiksen, Joe Biden, Humeyra Pamuk, Steve Holland, Simon Lewis, Jonathan Oatis
Organizations:
U.S, Reuters, U.S ., NATO, British, Danish, Thomson
Locations:
Lithuania, Norwegian, Vilnius, Ukraine, Russia, NATO, Washington