The TV star has taken in a woman in her 30s, her mother, and her baby girl amid the crisis in Ukraine.
Tarrant, who lives in Berkshire with his partner Jane Bird, was on the ITV show to discuss his new book and his career and host Alison Hammond asked how it was going with the family he had taken in.
He said it was "absolutely delightful".
"It's a mum, a daughter who is about 30 and a dear little baby, 10-months-old, and it's just amazing," he told Hammond and her co-host Dermot O'Leary.
Tarrant said that after watching what was happening he felt he had to step up and do something.
"They were sleeping on the floors in airports in Poland," he said.
"The little baby, it's 10 months, dear little girl just about trying to walk and you just think, 'What would your life be like if you were still back there' in that sick, evil world they're experiencing."
"It's horrific," he added.
With a brief interval for some smoke machine shenanigans, we asked Dermot if he could correctly answer the question he got wrong on Who Wants to Be a Millionaire 20 years ago... 👀 pic.twitter.com/RHwQVfbSm8
— This Morning (@thismorning) April 29, 2022
The Homes For Ukraine scheme allows UK residents, who have a spare room, to sponsor an individual or family from Ukraine to live with them for up to six months.
Since the government website launched on 18 March over 200,000 UK residents have registered their interest.
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