Washington: US President Barack Obama says intelligence agencies believe Iran is still “a year or more” away from producing a nuclear weapon, an assessment he acknowledged was at odds with Israel.

“Our estimate is probably more conservative than the estimates of Israeli intelligence services,” Obama said.

Obama’s comments on Iran came amid signs that long-standing tensions between the US and Tehran might be easing. In late September, Obama spoke by phone with President Hassan Rouhani, Iran’s new leader. The 15-minute call marked the first direct exchange between US and Iranian leaders in more than 30 years.

“Rouhani has staked his position on the idea that he can improve relations with the rest of the world,” Obama said. “And so far he’s been saying a lot of the right things. And the question now is, can he follow through?”

But Obama said Rouhani is not Iran’s only “decision-maker. He’s not even the ultimate decision-maker,” a reference to the control wielded by Iran’s supreme leader, Ayatollah Ali Khamenei.

Given the supreme leader’s broad influence, Israel has questioned whether Rouhani actually represents real change in Iran or just new packaging of old policies.

Khamenei said Saturday that he supported Rouhani’s outreach to the West, but at the same time called the US government “untrustworthy, arrogant, illogical and a promise-breaker,” according to comment summarised on his website.

Obama also put distance between US and Israeli assessments of when Iran might have the capacity to build a nuclear weapon. Israeli officials have said Iran is just months away from having the capacity and knowledge to build a bomb, while Obama said Tehran was a year or more away.

Israeli Justice Minister Tzipi Livni played down the differences.

“The question isn’t the timetable the question is how we get that result,” Livni told Israel’s Channel 10 TV.

Iranian Foreign Minister Mohammad Javad Zarif disputed Obama’s comments, repeating Iran’s claims that it is not seeking a nuclear weapon.

The US and Israel contend that Iran’s nuclear programme is aimed at building a bomb, while Tehran says it is enriching uranium for peaceful purposes.