The former prime minister said that he had been impressed by the former home secretary's attempt to reinvent himself after being forced to resign as health secretary after his affair with government advisor Gina Colangelo during the coronavirus pandemic was exposed.
Blair, 69, told The News Agents podcast: “When you’ve been through the wringer as he has, and you know, as a politician who’s got to a certain level in politics, he’s probably got quite a lot of courage to go and do something like that.
“And I mean, people can attack him or whatever ... But, you know, it takes a lot of courage to go do something like that. I wished him well from the outset.”
The former leader of The Labour Party defended Hancock's work as health secretary during the COVID-19 pandemic.
He said: "I worked with him a bit during the pandemic. He was working hard, they were all working hard on it.
“The government didn’t cause COVID. You can argue whether they should have dealt with it better or not, and so on, and you can make criticisms as you can with any country. The truth is we’re about in the middle of the pack as to how we handled it.”
Watch: Matt Hancock says thank you to all those who voted for him on I'm A Celebrity
Blair also said he could understand what Hancock meant when he said he was trying to reach a different part of the electorate by appearing on the show.
He said: “I don’t think people’s political views are going to be changed one way or another.
“But I think the problem with politics nowadays is how do you communicate with people when you’ve got a fragmented, media, social media, and when it’s quite difficult to get a message across to people who aren’t in your circle, because the way the media works today is essentially, it works by developing a constituency of people and essentially appealing to that constituency.
“And if you’re not careful, you don’t break out and go and talk to the people who disagree with you. So, I guess in that sense, he’s got a point. But it’s quite an extreme way of reaching the public.”
Hancock, 44, came third in the ITV jungle reality show.
He is still an elected MP for West Suffolk, meaning he is being paid an annual salary to serve his constituents.
Hancock has vowed to declare his I'm A Celebrity salary to Parliament and donate it to St Nicholas Hospice in Suffolk and causes supporting dyslexia.
As a result of his signing up to the show his parliamentary whip has been suspended, meaning he is not a member of the Conservative Party.
Parliamentary watchdog the Advisory Committee on Business Appointments (Acoba) has ruled his participation in I'm A Celebrity is a breach of the government's business appointment rules. But they have advised that no further action be taken.