Saudi Arabia cautiously welcomed on Monday the Geneva nuclear deal reached between Iran and world powers, saying "good intentions" could lead to a comprehensive agreement on Tehran's controversial atomic programme.

"This agreement could be a first step towards a comprehensive solution for Iran's nuclear programme, if there are good intentions," the Saudi government said in a statement.

The landmark deal reached Sunday would curb parts of Iran's nuclear programme in return for some relief from international sanctions.

Sunni-ruled Saudi Arabia has been locked in a decades-long rivalry with Shia-dominated Iran.

The government said a comprehensive solution should lead to the "removal of all weapons of mass destruction, especially nuclear, from the Middle East and the Gulf."

Such solution should be followed by "important steps" that would guarantee the right of all states in the region to use nuclear power for peaceful purposes, it added, the SPA state news agency reported.

The deal was reached following marathon talks in Geneva between Iran and the so-called P5+1 nations comprising the United States, China, France, Britain, Russia and Germany.

The West and Israel suspect Iran is pursuing a nuclear weapons capability alongside its uranium enrichment programme, which Tehran insists is entirely for peaceful purposes.