The former prime minister suggested "the will of the people is entitled to change"
Tony Blair has said that Britain must keep its "options open" following the vote to leave the EU as "the will of the people" can change.
"One of the reasons we must keep our options open is - yes, the referendum expressed the will of the people - but the will of the people is entitled to change," the former prime minister told the Sky News Murnaghan programme.
Asked if he meant there needed to be a second referendum or that Parliament could override the 23 June vote, Mr Blair responded: "I don't think you can override the settled will of the people but my point is very simple: it's 52 to 48.
"Supposing some weeks or months down the line, as it becomes clearer what we're moving to ... if it's clear that these terms are bad for us ... if we have major parts of business and the financial sector saying this is not a good deal for us, if people start to worry about their jobs, we should just keep our options open."
He added: "The vote was to leave the European Union ... but we have no idea what lies on the other side of that and there's a hugely complex negotiation that's now got to take place.
"We need to see exactly what is the offer - what does Brexit look like?"
"As a country, we should keep our options open because right now we really don't know what's on the other side," he said.
And he also said that since Vote Leave won the referendum their arguments are unravelling.
"Let's be very blunt about - some of the claims made for the Brexit case have somewhat collapsed," he said.
He also criticised Conservative leadership contender and Brexit campaigner Andrea Leadsom after it emerged she was previously against leaving the EU.
"You find Conservative people who were campaigning for Brexit saying a few years ago it would be a disaster for Britain to leave the EU, so you've got a very strange atmosphere around all this," he said.
When pressed about the upcoming release of the Chilcot report and calls for him to go to jail over his role in the Iraq war, Mr Blair responded: "I think it's best we wait for Wednesday and let's just see what the report brings ... then I can respond properly."
He said he would be "participating very fully" in discussions following report's release on Wednesday.
On Brexit, Mr Blair suggested it was best to hold off on invoking Article 50, which would formally begin the process of Britain's separation from the EU.
"There will be a limit to how long we can do that - but absolutely I think we should keep all our options open," he said.
Asked how long Britain should wait before triggering Article 50, he said: "Frankly my view is for as long as it takes before we can get an idea of what the other side looks like.
"Personally right now I'd have someone very senior - I'd even say the prime minister or the chancellor - visiting every capital in Europe, seeing what the room for manoeuvre is, seeing what they might really want, understanding their politics," he said.
"The most important thing right at this moment is to make sure that we shape the psychology and the thinking of the other 27 countries in Europe," he added.