BERKELEY HEIGHTS, N.J. (Reuters) - President Donald Trump lashed out at OPEC with a warning to stop manipulating oil markets and piled pressure on close U.S. allies in an interview that aired on Sunday with a threat to sanction European companies that do business with Iran.

FILE PHOTO: U.S. President Donald Trump delivers remarks at an event marking the 6-month anniversary of the package of changes to the tax code he signed into law, at the White House in Washington, U.S. June 29, 2018. REUTERS/Jonathan Ernst

The president, in an interview with Fox News’ “Sunday Morning Futures with Maria Bartiromo,” also said he would not complete a new NAFTA trade deal with Canada and Mexico until after the November congressional elections.

Trump, who is spending the weekend at his golf property in New Jersey, said in a tweet on Saturday that Saudi Arabia’s King Salman bin Abdulaziz Al Saud had agreed to produce more oil.

The White House later walked back the president’s comments, saying the king said his country can raise oil production if needed.

Oil prices rose on Friday on worries that U.S. sanctions against Iran would take away significant volumes of crude oil from world markets while oil demand worldwide increases.

Rising gasoline prices could create a political headache for Trump ahead of the November elections by offsetting Republican claims that his tax cuts and rollbacks of federal regulations have helped boost the economy.

On Fox, Trump directed blame at the Organization of Petroleum Exporting Countries, of which Saudi Arabia is a member. Asked if someone was manipulating oil markets, Trump said: “OPEC is and they better stop it because we’re protecting those countries, many of those countries.”

The president also had tough words for other U.S. allies. Earlier this year, to the chagrin of European partners, Trump said he would pull the United States out of the Iran nuclear agreement secured by world powers.

He said in the Fox interview that European companies would face sanctions if they traded with Iran now.

“Of course. That’s what we’re doing, absolutely,” he said.

Trump will leave for a trip to Europe later this month for a meeting with NATO allies, whom he has criticized sharply for paying too little for their joint defense.

Trade tensions are likely to overshadow that trip. Trump has imposed tariffs on steel and aluminum in response to what he calls unfair trade practices from Europe, Canada, and other allies around the world, who have responded with retaliatory sanctions in kind.

On trade, the president said in the Fox interview that he was not happy with the North American Free Trade Agreement and would not agree a new one until after the November elections.

“I want to wait until after the election,” he said.