A spokesperson for the prime minister and Ms Symonds said both the mother and baby are “doing very well”, and that the couple would like to thank the “fantastic” NHS maternity team.
The news of the birth comes just days after Mr Johnson returned to No 10 to resume his responsibilities – three weeks on from being discharged from St Thomas’ Hospital where he was briefly in intensive care suffering from coronavirus.
The announcement was greeted with well wishes from across the political spectrum, with Sir Keir Starmer posting on his official Twitter account: “Wonderful news. Many congratulations to Boris Johnson and Carrie Symonds.”
Matt Hancock, the health secretary, described it as a “moment of unalloyed joy” while the chancellor Rishi Sunak congratulated the couple, adding: “Great to hear Downing Street is getting a new resident.”
Justin Welby, the archbishop of Canterbury, said: “Congratulations and prayers for Boris Johnson and Carrie Symonds as they welcome their son into the world. Wishing them every blessing and happiness.”
The prime minister has previously suggested he intends to take paternity leave, although it is not known if this remains the case amid the coronavirus pandemic and critical decisions that need to be made at No 10 on the country’s next steps.
Ahead of the announcement, it was unclear for 24 hours whether Mr Johnson would be attending the weekly session of prime minister’s questions, facing Sir Keir at the despatch box for the first time.
Mr Johnson had been expected in the Commons for the first time since he fell ill with coronavirus last month – providing MPs and the new Labour leader with an opportunity to scrutinise his approach to the pandemic.
But on Wednesday – just two hours before the weekly session – a spokesperson for the couple said: “The prime minister and Ms Symonds are thrilled to announce the birth of a healthy baby boy at a London hospital earlier this morning. Both mother and baby are doing very well.”
Earlier this year the couple announced they were expecting a baby in the “early summer”, and that they had become engaged at the end of 2019.
Dominic Raab, the first secretary of state and foreign secretary, who had been deputising for the PM as he recovered from Covid-19, will stand in for Mr Johnson at prime minister’s questions later today.
On Monday, the prime minister delivered an address to the nation – his first public appearance since leaving hospital – claiming there were signs the country was “turning the tide” against coronavirus.
But he warned it was too early to relax the lockdown, suggesting the country was now facing the “moment of maximum risk”, and said the government was aiming to avoid a “second major outbreak” of coronavirus and more loss of life.
Speaking outside No 10, Mr Johnson described the virus that has claimed more than 20,000 lives in UK hospitals as “an unexpected and invisible mugger” and said that now was the moment “we have begun together to wrestle it to the floor”.
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