Boris Johnson’s leadership in the United Kingdom is dangling by a thread following the resignations of two of his most high-profile ministers, as well as numerous more top officials and ministerial aides, in the previous 24 hours.

Rishi Sunak, the British Finance Minister, resigned Tuesday evening, stating the government should be governed “fully, efficiently, and seriously.” Similarly, Health Secretary Sajid Javid quit in protest at Johnson’s leadership, which has been marred by controversy and scandal in recent months.

As a number of top Conservatives called on Johnson to resign, the government’s former Brexit negotiator David Frost joined the chorus, urging the prime minister to resign immediately. Frost joined other opponents of Johnson in a newspaper piece Wednesday, saying clearly that “it is time for him to resign,” adding that “if he goes on, he risks pulling the party and the government down with him.”

Despite calls to quit, the prime minister shows no signs of relenting. He reshuffled his ministerial team last night to cover the openings left by the surprise resignations.

Several ministers supported Johnson and expressed their support for him. Deputy Prime Minister Dominic Raab, Foreign Secretary Liz Truss, and Home Secretary Priti Patel are among those who will remain in the Cabinet.