The UK’s Supreme Court refused to let the Treasury intervene in a landmark court case over controversial car loans, dealing a blow to Chancellor Rachel Reeves who had sought to argue that the suit was hindering Britain’s regulatory environment.

Chancellor of the Exchequer Rachel Reeves will have to watch the Supreme Court’s hearing on motor finance claims from the sidelines it emerged yesterday, after the Treasury was refused permission to intervene in the high-stakes case.

The UK Supreme Court on Monday rejected a move by finance minister Rachel Reeves to intervene in a landmark case on car loan mis-selling, sending shares in lenders Close Brothers and Lloyds Banking Group sharply lower.