CERNOBBIO, Italy, Sept 5 (Reuters) – NATO members should not tolerate deliberate actions of hybrid war, ‌and the United States will stand by ‌countries as they deal with these incidents, Matthew Whitaker, the U.S. ​ambassador to NATO, said on Saturday.

Whitaker said last month’s attempted drone attack at Germany’s Leipzig/Halle Airport, which Berlin has blamed on Russia, was more worrying than ‌other recent incidents ⁠NATO members have faced due to Russian drones targeting Ukraine that strayed off course.

“Then ⁠you have what I would call the more concerning hybrid actions like we saw in Leipzig, like ​we have ​seen in Poland,” Whitaker ​said speaking on the ‌sidelines of a business conference in Italy.

NATO members must be prepared, vigilant and also deliver a strong message when they are challenged by these events, he said.

“If we can identify who’s doing it — which ‌Germany did — we make sure ​we express strongly that is ​unacceptable and we ​will not tolerate it,” Whitaker said.

Critical ‌infrastructure, including energy assets, could ​be targeted and ​should be monitored by national authorities, he added.

The response to these challenges is primarily national, ​but the United ‌States supports countries when they are dealing ​with these acts, he said.

(Reporting by Francesca Landini; ​Editing by Sharon Singleton)