Scotland Yard said last month that 50 referrals had been made to the criminal records office for fixed penalty notice (FPN) fines over parties in Downing Street and Whitehall.
In an update on Thursday, the Met police said its Operation Hillman team had now recommended 100 fines. The force said its investigation, into 12 separate events, remains ongoing.
No 10 said Boris Johnson has not been issued with another fine, after he was punished last month over his rule-breaking birthday party in June 2020.
The Liberal Democrats said the new fines showed the “shocking scale” of rule-breaking in government.
“Boris Johnson stood up in parliament and said Covid rules were followed in No 10 at all times,” said leader Sir Ed Davey. “Now 100 fines have been issued … it shows the shocking scale of the law-breaking in Johnson’s Downing Street and the extent of his lies.”
Labour’s deputy leader Angela Rayner said the government had “racked up the dubious distinction of receiving more fines on the prime minister’s watch than any other location.”
She added: “Boris Johnson made the rules, and then broke them at record-breaking scale. Britain deserves better.”
Dominic Cummings, pictured below, suggested that junior No 10 staff bitter at being fined for attending events they were told were lawful may get their revenge at the Covid inquiry.