White House's Navarro 'never heard' Trump ask China's Xi for help winning election

White House trade adviser Peter Navarro on Sunday said he was in the room with President Donald Trump and Chinese President Xi Jinping when they met, but never heard the U.S. president ask for China's help in winning re-election.

Navarro told CNN's State of the Union program that the explosive allegation made in a book by former national security adviser John Bolton was "just silly" given how tough Trump had been on China and its unfair trade practices.

"I never heard that. I was in the room," Navarro said, echoing remarks by U.S. Trade Representative Robert Lighthizer last week.