(Bloomberg) -- The lawyer behind a landmark ruling allowing the U.K. to change its mind on Brexit is planning a last-ditch challenge to the government’s plans for drug supplies if the country tumbles out of the European Union next month without a deal.

Jolyon Maugham, who runs an anti-Brexit group, is preparing to file a legal challenge over regulations covering the availability of medicines, he said in a statement on Tuesday.

His group, the Good Law Project, wants the government to consult over its plan, which would allow pharmacists to hand out different medications for the same condition in some circumstances during a serious drugs shortage.

“Lives are at stake and these measures need to be properly thought through – however long that takes. This is too important to be done in a hurry,” Maugham said by email.

The group will file a lawsuit unless the government cancels new rules that allow pharmacists to alter prescriptions, he said.

The Department of Health and Social Care didn’t immediately comment.

To contact the reporter on this story: Kaye Wiggins in London at kwiggins4@bloomberg.net

To contact the editors responsible for this story: Anthony Aarons at aaarons@bloomberg.net, Peter Chapman, Christopher Elser

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