The Gulf states face a greater threat from within their own countries than from outside forces such as Iran or ISIL, US President Barack Obama has said in an interview explaining the nuclear deal struck with Iran last week.

Speaking to the New York Times, Obama insisted the US was committed to GCC security but “a tough conversation” needed to be had with Gulf leaders over their internal issues.

The Arab states faced more pressing threats such as “populations that, in some cases, are alienated, youth that are underemployed, an ideology that is destructive and nihilistic, and in some cases, just a belief that there are no legitimate political outlets for grievances,” Obama said.

“And so part of our job is to work with these states and say, ‘How can we build your defense capabilities against external threats, but also, how can we strengthen the body politic in these countries, so that Sunni youth feel that they’ve got something other than [ISIL] to choose from.

“... I think the biggest threats that they face may not be coming from Iran invading. It’s going to be from dissatisfaction inside their own countries. ... That’s a tough conversation to have, but it’s one that we have to have.”

Obama also said he would tell Gulf states they needed to be more active in addressing regional crises.

"I think when you look at what happens in Syria, for example, there's been a great desire for the United States to get in there and do something," he said during the interview published on Sunday.

"But the question is: Why is it that we can't have Arabs fighting the terrible human rights abuses that have been perpetrated, or fighting against what Assad has done?" he added, referring to Syrian President Bashar Al Assad.

Obama said last week he would meet the six GCC leaders this spring at his Camp David retreat outside Washington, partly to discuss their concerns about the emerging nuclear agreement with Iran.

The GCC, which sees Iran as its main regional rival, has repeatedly suggested it would seek its own atomic weapons if Tehran ever did the same.

Prince Turki Al Faisal, who has previously served as head of Saudi intelligence and Riyadh’s ambassador to Washington and London, told the BBC last month: "I've always said whatever comes out of these talks, we will want the same.

"So if Iran has the ability to enrich uranium to whatever level, it's not just Saudi Arabia that's going to ask for that. The whole world will be an open door to go that route without any inhibition, and that's my main objection to this P5+1 [the six world powers] process."

The Arab states, as well as Israel, are concerned the preliminary deal with Iran allows the Shia state to maintain its nuclear program.

Israeli Prime Minister Benjamin Netanyahu told CNN the deal should have included a provision to prevent Iranian efforts to develop an international ballistic missile, rather than pause it for 10-15 years.

“Those missiles are only used for you,” he said, referring to the US. “No one is asking Iran in this deal to stop its aggression in the region.”

Obama, however, argued the deal was in line with his administration’s foreign policy methods in Cuba and Burma, countries the US considered were such low risk it was worth improving relations, which also would improve the lives of those countries’ citizens and potentially reduce the potential for hostility against the US.

“If it turns out that it doesn’t lead to better outcomes we can adjust our policies,” he told the New York Times.

“The same is true with respect to Iran, a larger country, a dangerous country, one that has engaged in activities that resulted in the death of US citizens, but the truth of the matter is: Iran’s defence budget is $30 billion. Our defence budget is closer to $600 billion.

“Iran understands that they cannot fight us… You asked about an Obama doctrine. The doctrine is: We will engage, but we preserve all our capabilities.”