Coronavirus: British PM's message to New Zealand after being admitted to hospital with COVID-19

British Prime Minister Boris Johnson says he is thinking of New Zealand during the COVID-19 pandemic.

Johnson, 55, tested positive for COVID-19 on March 28 and was self-isolating at home but after his symptoms worsened he was put into critical care on Sunday.

Prime Minister Jacinda Ardern said in her Tuesday press conference that she had sent him a message after learning of his hospital admission.

"I do want to acknowledge the news this morning that British Prime Minister Boris Johnson is currently in intensive care. 

"Upon learning the prime minister had tested positive for COVID-19 some days ago now I sent a message to him to pass on New Zealand's best wishes.

"He replied to that message and said that his thoughts were also 'with all our friends in New Zealand'".

Ardern says it is important for everyone to support each other through the global pandemic.

"This more than ever is a time when every nation is connected and I know we will want everyone in the UK especially the Prime Minister to know that we are thinking of them."

Johnson was admitted to hospital on Sunday (local time) as a "precautionary step" when his symptoms turned persistent 10 days after testing positive.

The spokesperson for 10 Downing Street said in a statement on Monday Johnson was moved to intensive care at St Thomas' Hospital in London after his condition worsened.

"On the advice of his medical team, he has been moved to the intensive care unit at the hospital.

"The PM has asked Foreign Secretary Dominic Raab, who is the First Secretary of the State, to deputise for him where necessary.

"The PM is receiving excellent care, and thanks to all NHS staff for their hard work and dedication."

Fellow politicians have been sharing their thoughts on social media including Ex-UK Prime Minister Theresa May who highlighted that coronavirus can affect anyone.

"My thoughts and prayers are with @BorisJohnson and his family as he continues to receive treatment in hospital," she posted on Twitter.

"This horrific virus does not discriminate. Anyone can get it. Anyone can spread it. Please #StayHomeSaveLives."

Another former Prime minister David Cameron also wished Johnson well on Twitter.

"Thinking of @BorisJohnson and his family tonight. Get well soon. You are in great hands and we all want you safe, well and back in @10DowningStreet."