UK's Johnson does not have pneumonia - spokesman

Johnson remained in intensive care in St Thomas' hospital in London after being admitted when his coronavirus symptoms worsened over the weekend. The pound, already higher on the day, rose again to be 1% higher against the dollar at $1.2354, while the FTSE 100 share index was up 3%.

"The prime minister has been stable overnight and remains in good spirits. He is receiving standard oxygen treatment and breathing without any other assistance. He has not required mechanical ventilation or non-invasive respiratory support," the spokesman said.

Since first being admitted to St Thomas’ on Sunday evening, Johnson had received oxygen through a non-invasive mask and had not needed a ventilator, officials said.

Questions had been raised about the transparency of Downing Street's communications on Johnson's health. Claims that his condition had not deteriorated came under increased scrutiny after it emerged that a bed at St Thomas’ was being prepared for the prime minister as early as last Thursday.

Aides had also insisted that Johnson's condition was mild just before he entered hospital, before changing course on Monday and describing his cough and temperature as “persistent”.

There was further confusion when Foreign Secretary Dominic Raab, who took charge in the prime minister's absence, on Monday insisted that Johnson was still "leading and giving instructions as and when required”, but then admitted he had not not having spoken to Johnson since Saturday.

Forced on to the defensive, Johnson's spokesman on Tuesday said aides had been "fully frank with (the media) throughout".

"We have issued you with regular updates on the prime minister’s health," his spokesman said.

"His condition worsened yesterday afternoon. A decision was taken that he needed to be moved to an intensive care unit at around 7pm. We informed you all as soon as was practically possible. We have a commitment to be as transparent as we can be throughout this process."