LONDON (AFP) - World leaders hailed the Iran nuclear deal on Tuesday, with Barack Obama envisioning a "new direction" and Vladimir Putin voicing a global "huge sigh of relief" - though Israel criticised it as a "historic mistake".

Major international powers who thrashed out the agreement with Teheran said they hoped Iran would build on the opportunity to come in from the cold.

However, Israeli Prime Minister Benjamin Netanyahu hinted he remained ready to order military action against Iranian nuclear sites.

US President Obama said the agreement offered a chance to reset vexed relations with Teheran.

"Every pathway to a nuclear weapon is cut off," he said.

"This deal offers an opportunity to move in a new direction. We should seize it."

But US House Speaker John Boehner, a Republican, said the agreement would "embolden" Teheran and likely "fuel a nuclear arms race".

Sealed in Vienna after a 13-year stand-off, the deal was reached between Teheran and the United States, Russia, China, Britain, France and Germany.

Russia's President Putin hailed the deal as a "firm choice for stability and cooperation."

"The world has breathed a huge sigh of relief," he said.

Putin said Moscow would "do everything in its power" to ensure the agreement worked.

Russian Foreign Minister Sergei Lavrov said the deal would "make the situation in the Middle East healthier".

The Vienna agreement is aimed at ensuring Iran does not obtain a nuclear bomb, in return opening up Tehran's sanctions-stricken economy, thereby potentially ending decades of bad blood with the West.

Iran has always denied Western accusations that its civil nuclear programme was a cover for acquiring nuclear weapons.

ISRAEL UNMOVED

Netanyahu called the deal a "historic mistake" marked by "huge compromises".

"We did commit to preventing Iran from acquiring nuclear weapons, and this commitment still stands," he added, in what was seen as a thinly veiled threat of pre-emptive strikes against Iranian nuclear sites.

"Israel is not bound by this deal with Iran because Iran continues to seek our destruction."

Through sanctions easing, "Iran will get hundreds of billions of dollars with which it will be able to fuel its terror machine," Netanyahu added.

Obama is to speak to leaders in Israel and Saudi Arabia, who are also sceptical.

United Nations Secretary-General Ban Ki-moon said the agreement could help resolve the Middle East's security challenges.

"It could serve as a vital contribution to peace and stability both in the region and beyond," he said.

British Prime Minister David Cameron said the deal would help "make our world a safer place" and said Iran now had a "real opportunity" to benefit from the pact economically.

Germany's Vice-Chancellor and Economy Minister Sigmar Gabriel now plans to visit Iran soon.

"There is great interest on the part of German industry in normalising and strengthening economic relations with Iran, all the more so after today's agreement," his ministry told AFP.

REGION WELCOMES AGREEMENT

French President Francois Hollande said "the world is making headway," and urged Teheran to help world powers end the Syrian conflict.

"Now that Iran will have bigger financial capabilities - as there will no longer be sanctions - we must be extremely vigilant on what Iran will be," he said.

Syria's President Bashar al-Assad said his key ally Iran had "achieved a historic victory" with the agreement.

He congratulated Iran's supreme leader Ayatollah Ali Khamenei on a "major turning point in the history of Iran, the region and the world".

Iran's neighbours welcomed the deal.

Afghanistan said it welcomed efforts aimed at "strengthening of peace and stability in the region", while Pakistan said that confidence-building measures over Iran's nuclear programme "auger well for peace and security in our region."

Turkish Foreign Minister Mevlut Cavusoglu said the deal would boost the regional economy.

Alongside him in Ankara, his Iraqi counterpart Ibrahim al-Jaafari also supported the deal and emphasised keeping "doors of dialogue open".

The agreement must "be implemented for the region to reach stability," he added.

The United Arab Emirates said Iran could play a significant regional role if it "stops interfering in the internal affairs of countries like Iraq, Syria, Lebanon and Yemen."

UAE wants to see "a genuine desire for Iran to help extinguish fires devouring the region", namely "sectarianism, extremism and terrorism", an official said.

Meanwhile the Vatican hoped the agreement would "bear fruit" which would extend beyond simply Iran's nuclear programme.