"If the will of the people shifts, why shouldn't we recognise that?" said Blair on Radio 4's "The World This Weekend" programme.
"The country should carry on being engaged in this debate, it should carry on expressing its view. Yes right now, it's clear, we're leaving. But we don't know what we are going to. We should keep our options open."
When questioned over whether "keep our options open" meant a second EU referendum, Blair did not outright say no. Instead he said, "it means whatever we decide it should mean as we see how this debate develops."
On June 23, 51.9% of Brits voted for a Brexit in the referendum on European Union membership versus 48.1% who voted for Britain to stay within the EU. The turnout was 72.2% of the 46,499,537 people who were entitled to take part in the vote. This is a record for a UK poll.
However, since then, anger has swirled around the Brexit camp after allegations that the politicians in charge of the Leave campaign have already backtracked on promises, including that £350 million ($467 million) a week would go to the NHS once Britain stopped making payments to the EU and that there would be a limitation on immigration.
This weekend, thousands of people marched across London in protest of the Brexit result of the referendum, with many calling for a second referendum.