The British prime minister told Sir David Frost, during an exclusive interview aired by the channel on Friday, that Tehran must be prepared to change its behaviour.
In an interview that touched on many subjects, Blair also admitted that the invasion of Iraq was a mistake.
Responding to a question from Frost that the conflict had been a disaster from the start, he said "it has", before insisting he was right to remove Saddam Hussein from power.
Blair also urged Iran and Syria to do more to curb the violence in Iraq but said that the two "have different interests in the region."
'Same page'
He said: "We have to go out there, ourselves and the Americans, and say we are not against you because we believe we should decide who governs Iran or we should decide who governs Syria.
"What we're saying to you is very clear ... If you are prepared to be part of the solution there is a partnership available to you, but at the moment ... you are behaving in such a way that makes a partnership impossible."
Blair has previously committed himself to bringing peace to the Middle East, but during the interview he did not immediately endorse a new peace proposal initiated by France and Spain.
"It's good to have everyone on the same page but its really about making sure that we make progress to the two-state solution," he said.
He said it was vital that the international community "manages to get into a situation where we are negotiating about the details of peace rather than looking at the appalling consequences of conflict".
The British prime minister has been in office for nine years and is expected to step down within months.
Blair's legacy
Blair has said that he wants a new peace deal in the Middle East to be his legacy and warned that the greatest challenge facing with world now is "religious extremism".
"The fundamental political difference is less to do with the traditional left-right politics ... it is whether countries are open, whether they are tolerant, whether they embrace people of different views and different faiths or whether they are closed societies," he said.
Marwan Qabalan, a political analyst from the University of Damascus in Syria, told Al Jazeera that Tony Blair's interview contained many contradictions and indicated that Britain and the US needed to decide on a common policy towards Syria and Iran.
He said: "It might be in the end that they [Britain and the US] have to decide if Syria and Iran are supporting the insurgency or whether Syria and Iran have real influence in Iraq, so that they can be getting involved in the political process to stabilise that country [Iraq]."
Source : aljazeera.net