House Intelligence Committee Vice Chairman Adam Schiff said Wednesday that President Donald Trump's "Twitter diplomacy" will not be effective with North Korea after its firing of a long-range missile Tuesday that could reach Alaska.
"This is going to be most likely the biggest national security crisis of the president's term," the California Democrat told Jim Sciutto on CNN. "There is a lot more than we can do.
"It's not going to be Twitter diplomacy," he added. "We will have to put more pressure on China."
Schiff also slammed Trump's tweet earlier Wednesday about Beijing's increased trade with North Korea, calling it "very dangerous saber-rattling" that could embolden dictator Kim Jong Un.
He called on Trump to deal with China "in a very matter-of-fact way, not a provocative way" – telling Beijing what steps the U.S. would take unless it put more pressure on North Korea.
"It's going to be much more effective than tweeting the Chinese president," Schiff said.
On Trump's meeting Friday with Russian President Vladimir Putin, the representative said the president must tell Putin his country's meddling in U.S. elections was not acceptable.
"He has to tell Putin that we're not going to tolerate any country interfering with us and our elections."