British Prime Minister Boris Johnson and his partner Carrie Symonds have named their son Wilfred Lawrie Nicholas Johnson in honour of their grandfathers and the doctors who treated the Prime Minister for coronavirus.

The birth came just days after Mr Johnson returned to work following his hospitalisation for COVID-19 treatment and isolation.

Ms Symonds announced the name on Saturday on Instagram beside a picture of her and the boy, who already has thick hair resembling the blond thatch of his father.

Ms Symonds, 32, said Wilfred, who was born on Wednesday, was named after Johnson's grandfather, while his second name came from her grandfather Lawrie.

The choice of Nicholas, Ms Symonds said, was a nod to Nick Price and Nick Hart — two doctors who the couple have praised for saving Mr Johnson's life at St Thomas' hospital last month.

"I couldn't be happier," Ms Symonds said, adding her thanks to the maternity staff of University College London Hospital.

"My heart is full."

'We are honoured and humbled'

Mr Johnson, 55, returned to work on Monday after recuperating from COVID-19, which had left him gravely ill in intensive care at the peak of the coronavirus outbreak.

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He thanked the doctors at St Thomas' hospital who, he said, had "saved my life, no question".

"We are honoured and humbled to have been recognised in this way," said Dr Price, director of infection at Guy's and St Thomas' NHS Foundation Trust, and Professor Hart, director of respiratory and critical care.

Ms Symonds, a former public relations executive, also had symptoms of the virus but recovered more swiftly. She had said in February that the baby was due in early summer.

Mr Johnson, who was present at the birth, will take a short period of paternity leave later in the year.

Boris Johnson's complicated past

Ms Symonds and Mr Johnson have been living together in Downing Street since he became prime minister in July.

They announced in February they were expecting their first child and that they were engaged to be married.

Once dubbed "Bonking Boris" by Britain's tabloid media, Mr Johnson has had a complicated private life.

He has been divorced twice and refuses to say how many children he has fathered.

He was once sacked from the Conservative Party's policy team while in opposition for lying about an extra-marital affair.

In 2013, when Mr Johnson was mayor of London, appeal court judges ruled that the public had the right to know he had an extra-marital affair with a woman who gave birth to his daughter.

Mr Johnson's previous marriage was to Marina Wheeler, a lawyer.

They had four children together but announced in September 2018 that they had separated. They divorced earlier this year.

Few British leaders have had babies while in office.

David Cameron's wife Samantha gave birth to their daughter, Florence, in 2010, and Tony Blair's wife Cherie gave birth to their son, Leo, in 2006.

Before that, Frances, the wife of John Russell, a 19th-Century Whig and Liberal politician, gave birth to two children in 1848 and 1849 while he was in office.

ABC/Reuters

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