Boris Johnson is not expected to take in a Ukrainian refugee into No10 due to "unique circumstances".
Downing Street said the Prime Minister would be unlikely to be able to host families fleeing war at his London residence due to security concerns.
Brits will be able to put up refugees from the Ukraine conflict in their homes under a new sponsorship route called "Homes for Ukraine".
Levelling Up Secretary Michael Gove is expected to set out further details later today, with a website going live shortly for people to register interest.
Hosts receive a £350-a-month 'thank you' payment and will be expected to commit to a minimum of six months.
Asked if the PM would house a refugee, his official spokesman said: "As you'll know there are specific challenges around security on having someone in No10 but various ministers have been asked about this today and obviously it will come down to individual circumstances.
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"This is a significant commitment and it will depend on people's circumstances on what's right for them."
Pressed on whether the answer was no, the spokesman: "I think for security reasons you would expect we'd be unable to facilitate that in No10."
The Prime Minister's Chequers retreat in Buckinghamshire also looks off the cards as it is a privately-run trust.
The spokesman said No10 “both office space and private residence”, which complicates the situation.
He added: “I think the public would accept there’s a unique circumstance with regard to security for the Prime Minister.”
Health Secretary Sajid Javid signalled that he would not be able to take someone in, saying that it would be difficult for him to "offer the time".
But Transport Secretary Grant Shapps said that he would open his home.
He tweeted: "We've spent the past few weeks as a family discussing the devastating situation in Ukraine, and so we intend to apply today to join other UK households in offering our home to provide refuge to Ukrainians until it is safe for them to return to their country."
From today, Brits will be able to register their interest for the scheme - which is separate to the family route which allows Ukrainians with blood ties to the UK to apply for visas.
Sponsors will need to prove they can provide unoccupied accommodation for six months.
Applications will open online on Friday for both Ukrainians and Brits who want to host refugees.
Charities and non-governmental organisations are expected to help connect sponsors and refugees, rather than the Government acting as an intermediary.
It is understood that this approach was chosen to speed up the process in response to the spiralling refugee crisis.
More than 2.5 million people have fled the Russian invasion in Ukraine according to the UN refugee agency.
