The bill would give police wide-ranging new powers
His words came as ministers prepared to battle to overturn the 10 defeats inflicted by the House of Lords on the government's controversial anti-terrorism bill.
Mr Blair told MPs it was important not to "let the time that has elapsed since 11 September dim our outrage" at the terrorist atrocities in the United States.
He reminded them of the "absolute certainty" shared on all sides of the House, at the time, that stronger laws were needed to "fight terrorism properly".
'Ping-pong'
Speaking at Prime Minister's Question Time, Mr Blair told MPs: "I do hope, even at this stage, that all sides of the House will support these measures and allow us to put them in place as soon as possible so that we can successfully prosecute the war against terrorism at home and abroad."
The bill returned to the Commons on Wednesday and if the government uses its huge majority to reverse the Lords' changes, days of parliamentary "ping pong" between the two Houses could ensue.
Earlier, home Secretary David Blunkett met shadow home secretary Oliver Letwin and Lib Dem home affairs spokesman Simon Hughes to discuss the plan ahead of Wednesday's debate.
The two opposition parties say they hope to reach a consensus with the government over the changes they want made to the proposed legislation.
No compromise
But Downing Street is saying ministers have already made several concessions and it is not prepared to drop contentious measures such as a new law outlawing incitement of religious hatred.
The prime minister's official spokesman told reporters: "What the government is not prepared to do is gut the bill.
"What you will see is the bill coming back to the Commons and it will be sent back to the Lords."
On Wednesday, Mr Blunkett is meeting US attorney-general John Ashcroft about the measures proposed in the bill as Mr Ashcroft begins a European tour.
If the Commons rejects the Lords' amendments as expected, the bill will go back to the upper house at the start of a battle that could last for days.
Ministers cannot use the Parliament Act to force the measures through the Lords unless they reintroduce the bill in the next parliamentary session, which starts late next year.
The ten amendments
The government's proposals have provoked outrage from all sides in the Lords.
Peers have accused ministers of using the terrorist attacks of 11 September as an excuse to push through draconian new measures limiting traditional freedoms.
In the past eight days, peers have:
On Tuesday, peers voted through a tenth amendment, offered by ministers, giving Parliament a chance next year to debate a voluntary code of practice on the retention of phone bill and e-mail data.
This controversial section of the bill would require telephone companies and internet service providers to accumulate information about their customers.
Commons leader Robin Cook has insisted the anti-terror bill would be on the statute books by the weekend, in time for an EU summit at Laeken, near Brussels.