Allegations of “intimidation” from the government surfaced on Wednesday, with top Tory William Wragg urging colleagues to contact the Metropolitan Police if they have faced any threats.
“The reports of which I am aware would seem to constitute blackmail,” Mr Wragg said during a statement.
Mr Johnson, however, has denied any suggestion of wrong-doing.
“I see no evidence to support any of those allegations,” the prime minister said.
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