John Bolton at Downing Street in London | Tolga Akmen/AFP via Getty Images Brexit Files Insight Trump envoy’s cheap Brexit promises Trade experts say John Bolton’s proposal just isn’t realistic.

John Bolton's proposal for sectoral U.S.-U.K. trade deals post Brexit has caused excitement in London, but cynical trade experts are not convinced.

Promises come cheap, they point out. When the U.S. asks Britain to sign on the dotted line, it will be Congress, U.S. farmers, and Trade Representative Robert Lighthizer who dictate the conditions, not Trump's national security adviser.

“What Bolton is proposing is not realistic," said Sam Lowe from the Centre for European Reform. "Why would Congress sign off on anything that doesn’t have agriculture included?”

Any trade deal with the U.S. needs to be ratified by Congress — where Democrats have a majority in the House of Representatives, and interest groups, in particular farmers, work to make sure any trade deal is in their favor.

"All Congress cares about is agriculture and dismantling the EU’s regulatory approach to food and chemicals,” Lowe argued. Any deal that falls short of that would not be ratified, regardless of Bolton's assurances.

Case in point: Congress has been holding up Trump's new USMCA deal with Canada and Mexico for months over dairy exports, lumber tariffs, and weak labor rights protections. It has made clear the U.S. won't even consider negotiating a trade agreement with the EU that doesn't include market openings for U.S. beef and chicken.

Bolton did not mention this inconvenience during his visit in London, likely because he had other goals in mind.

“For Bolton, the promise of a trade deal is a carrot to get U.K. cooperation on security issues,” Lowe said. The need for Boris Johnson's administration to show that Brexit will be a success has not gone unnoticed in Washington. Promising trade deals gets Bolton friends in Downing Street without costing anything.

“Remember that Bolton is not a trade expert. All he cares about is getting leverage to get the U.K. to follow the U.S. on Huawei, Iran and China.”

David Henig, director of the U.K. Trade Policy Project, pointed out another flaw in Bolton's proposal: "Partial trade deals that reduce tariffs in one sector are not legal under WTO rules."

While "Trump and Bolton have shown before that they care little for WTO rules, the U.K. on the other hand needs a well-functioning WTO," he added. It's what London will have to rely on to trade with the EU and other countries if it leaves the bloc without a deal.

A Department for International Trade spokesperson said: “We have already laid the groundwork for an ambitious, creative trade deal with the U.S. and are working hard to take advantage of the golden opportunity to increase trade between our countries as we leave the EU. We will set out our approach to negotiations in due course.”

So a trade deal along Bolton's lines is unlikely to ever see the light of day. As Lowe put it: "The U.S. didn’t get to where they are in the world by being unnecessarily nice to countries that are slightly desperate.”

This article has been updated.

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