LONDON -- President Trump will head to Brussels next week for a NATO summit and then Sicily for the G7 economic summit. So how do Europeans view the American president?

"There's a sense of horrified fascination" and fear, says Jonathan Powell, who ran the British prime minister's office during the Tony Blair years, and who knows about dealing with U.S. presidents.

When they're preoccupied with political intrigue at home, he says, foreign leaders can't rely on them.

"If this is going to be the next two or three years, totally consumed with these issues in Washington and unable to focus on international relations, that leaves a very serious vacuum," Powell says.

Even Russian President Vladimir Putin joked about President Trump's meeting with Russian foreign minister Sergey Lavrov. CBS News

It's a vacuum they're trying to avoid at NATO, which President Trump will visit next week. Officials there are reportedly planning to put strict time limits on discussions about military spending and fighting terrorism so the president doesn't tune out.

But if there's a sense of anxiety, there's a sense of humor regarding the president, too. Mr. Trump has long been the butt of jokes. Now satire shows find the material irresistible.

TV satire is one thing. But when Vladimir Putin starts dropping one-liners about you...

Putin joked that he'd have to reprimand Russian Foreign Minister Sergey Lavrov for not sharing secrets President Trump spilled in the Oval Office with Russian intelligence, adding that's "very bad of him."

Lavrov seemed to find it hilarious.

It's how you tell 'em.

What European leaders have historically wanted from U.S. presidents is consistency and engagement. The fear being privately expressed by some officials here is that this president is embarking on his first foreign trip with his mind elsewhere.