Hamas must accept Israel's right to exist before there can be progress toward peace in the Middle East, Prime Minister Stephen Harper repeated Friday.

And the current crisis in the region will get worse unless militants release three Israeli soldiers, he said after meeting British Prime Minister Tony Blair in London.

Tony Blair greets Stephen Harper outside the British PM's official residence in London.
Tony Blair greets Stephen Harper outside the British PM's official residence in London.
(Matt Dunham/Associated Press)
"Escalation is inevitable" unless the soldiers are freed, he said. "That's the specific problem," while Hamas's failure to accept Israel is a more general issue.

The two leaders' main topic of conversation was the current crisis in the region, which has seen Israel blockade Lebanon and send troops into Gaza following the capture of three Israeli soldiers by the militant groups Hezbollah and Hamas.

After the meeting, Blair said he believes the only hope for lasting peace in the Middle East is for all parties to get back to the "road map," a step-by-step peace plan, because it represents "the only chance of peace and stability."

But Harper said there can be no progress on that plan until Hamas, which now forms the government in the Palestinian territories, accepts Israel's right to exist.

He described Israel's response following the capture of the three soldiers on Israeli soil as "measured" self-defence.

While Harper and Blair differ on what Harper called nuances, the Canadian leader is more at odds with the French and Russian leaders he will meet in the coming days. Both of them have criticized Israel's actions.

The meeting with Blair started Harper's first major overseas tour since he became prime minister following the January election.

Leaders discuss Kyoto

The leaders also talked about global warming. Harper said Canada isn't abandoning the Kyoto process, even though the government has said Canada's targets to cut greenhouse gas emissions are not realistic.

Blair is a key supporter of the accord. 

Harper met the Queen in London, and will attend a meeting of the G8 leaders in Russia on the weekend.

That meeting's formal agenda, which includes energy security and education, is expected to be overshadowed by the Middle East crisis.

With files from the Canadian Press