BRUSSELS — NATO Secretary-General Jens Stoltenberg will remain in his role for an extra year to help steer the 30-nation military organization through the security crisis sparked by Russia’s war on Ukraine.

Stoltenberg tweeted Thursday that he is “honored” by the decision of NATO leaders to extend his term until Sept. 30, 2023.

“As we face the biggest security crisis in a generation, we stand united to keep our alliance strong and our people safe,” he said.

The former Norwegian prime minister was named to NATO’s top civilian post in October 2014. It’s the second time that his term of office has been extended. His mandate was due to expire in September.

In February, Norway’s government appointed Stoltenberg as head of the Scandinavian country’s central bank and said it hoped he could start in his new role around Dec. 1.

In Oslo, Finance Minister Trygve Slagsvold Vedum confirmed that Stoltenberg had resigned from the job. Temporary governor Ida Wolden Bache has been nominated in Stoltenberg’s place and her appointment is expected to be confirmed later Thursday.

“Of course I would like to see Jens Stoltenberg become our next central bank governor, but we are in the middle of a dramatic situation in Europe and I have great understanding that he prioritizes continuing in the important role he has in NATO,” Slagsvold Vedum said.

Stoltenberg, 63, has described Russia’s war on Ukraine as “the most serious security situation we have been in for decades.”

Stoltenberg has been praised for steering NATO through a difficult and divisive period under the Trump administration, when the U.S. threatened not to come to the aid of member countries that weren’t spending enough on defense.

Speaking to reporters on an Air Force One flight to Brussels on Wednesday, U.S. National Security Advisor Jake Sullivan said that President Joe Biden “thinks very highly of Secretary-General Stoltenberg.”

“They’ve developed a relationship of trust,” Sullivan said. “Secretary-General Stoltenberg has played an instrumental role in helping secure the powerful unity you’ve seen at NATO through this crisis.”

Stoltenberg was twice prime minister in Norway — from 2005 to 2013 and from 2002 to 2014 — and he also served as finance minister, and industry and energy minister.

Norwegian Prime Minister Jonas Gahr Støre told Norwegian news agency NTB that Stoltenberg had done “a solid job” as NATO chief. “Never before has the alliance been stronger, and never before in the alliance’s history has unity been more important.”

Wolden Bache was due to be formally be named the central bank chief later Thursday for a six-year term.

“Norges Bank has great respect for Mr Stoltenberg’s decision made in the light of his very important responsibilities as Secretary General of NATO,” she said.