Americans should “be rooting” for President Donald Trump at next week’s U.S.-North Korea summit on denuclearization, former President Bill Clinton said Thursday.

“I think we should be rooting for [Trump] to succeed with the North Korea negotiations,” Clinton said in an interview with PBS NewsHour managing editor and anchor Judy Woodruff.

Trump and North Korean leader Kim Jong Un are meeting June 12 in Singapore to discuss ending the regime’s nuclear weapons program — a goal that has eluded previous U.S. presidents, including Barack Obama, George W. Bush and Clinton.

The summit could be successful even if it doesn’t produce a full denuclearization deal, Clinton said, so long as North Korea makes other commitments such as allowing inspectors to monitor its nuclear weapons program.

Next week’s talks, at a resort on Sentosa Island, will be the first ever meeting between a North Korean leader and sitting U.S. president. Clinton called South Korean President Moon Jae-in a “genius” for helping broker the talks.

Trump has expressed optimism ahead of the summit, while cautioning that talks might not result in a final deal and could take longer than one day. CNN reported Thursday that Trump and Kim could meet for a second day if the first day of negotiations goes well.

“Anything we can do to reduce that threat [of North Korea’s nuclear weapons program] is a positive thing,” Clinton said.

Clinton spoke to the NewsHour alongside best-selling author James Patterson, with whom he co-wrote “The President is Missing,” a thriller about a fictional president’s response to a cyber attack. The book was released this month, putting Clinton back in the spotlight two years after his wife, former Secretary of State Hillary Clinton, was defeated by Trump in the 2016 presidential election.

Other highlights from the interview: