The World Trade Organization has just authorized the U.S. to go ahead with its tariffs worth billions of dollars on the European Union — that’s “a big deal” that would hopefully bring both sides to the negotiating table, said a former high-ranking trade official under President Donald Trump.

But Washington and Brussels have not achieved much in their past trade negotiations, so the U.S. tariffs on $7.5 billion of European goods could stay in place for many months, said Clete Willems, who was deputy director of the National Economic Council, told CNBC.

“It’s a big deal: $7.5 billion is the largest retaliation number that the WTO has ever authorized. So, it’s a big victory for the United States,” said Willems.

“At the end of the day, what they’d like to do is use these tariffs for leverage to get a negotiated outcome,” he said. “But I do think that the two sides haven’t worked together particularly well when it comes to trade negotiations lately and it may take some time for them to work through these issues ... so you are going to see these tariffs in place for some period of months.”