LONDON — The London School of Economics says some of its academics will no longer be allowed to advise the U.K. government on Britain’s exit from the European Union because they are not British citizens.

Sara Hagemann, an assistant professor at the school’s European Institute who is Danish, said government representatives told her that she and her non-UK colleagues “no longer qualify” as expert advisers.

A memo to staff from LSE interim director Julia Black, obtained Friday by The Times of London newspaper, said “the Foreign Office have advised us that they will be issuing tenders to contract for advisory work, but that only U.K. nationals will be eligible to apply.”

The university said in a statement that “any changes to security measures are a matter for the U.K. government.”

It said a group of fewer than 10 London School of Economics experts had been giving the government advice on Brexit.

“We believe our academics, including non-U.K. nationals, have hugely valuable expertise, which will be vital in this time of uncertainty around the U.K.’s relationship with Europe and the rest of the world,” it said.

The Foreign Office said there had been no policy change since the referendum. It said people who work with the government “may require security clearance depending on the nature and duration of their work.”

Britain voted in June to leave the 28-nation European Union. A desire to control immigration — impossible under the EU’s principle of free movement among member states — was a key issue for many voters.

Formal exit talks have yet to begin, but many in the business and academic spheres accuse the Conservative government of harming Britain’s international reputation with hard-line comments about immigration and relations with the EU.

Home Secretary Amber Rudd drew strong criticism this week when she said companies could be forced to disclose what percentage of their workforce was from other countries. She later said the government was not committed to the idea.

Nick Clegg, a spokesman on Europe issues for Britain’s Liberal Democrats party, said the decision about the academics was “utterly baffling.”

“This is yet more evidence of the Conservatives alarming embrace of petty chauvinism over rational policymaking,” Clegg said.