Iran nuke programme: World powers say significant differences remain

Key players involved in talks on Iran's nuclear programme have warned of there being big gaps between Iran and the world powers over the latter's nuclear capabilities.

According to the BBC, the warning comes with only a week left to strike a deal.

Arriving in Vienna for the talks, U.S. Secretary of State John Kerry said significant differences between Iran and the world powers remain.

This view was also echoed by France and the UK.

An Iranian envoy also said it was not clear if major gaps could be bridged.

The talks seek to persuade Iran to limit its nuclear programme in exchange for the lifting of sanctions.

Discussions on Sunday have been inconclusive.

There is growing speculation that the 20 July deadline for an agreement will need to be extended.

An interim deal was reached last year. However, the parties have been unable to reach agreement on imposing long-term restrictions over Iran's uranium enrichment and plutonium production - processes that could yield material for nuclear warheads.

World powers suspect Iran is seeking atomic weapons. Iran strongly denies the charge, insisting that it is enriching uranium to fuel its power plants, and for medical needs.

A deal could see the lifting of oil and trade sanctions on Iran.

The talks in Vienna bring together Iran and the P5+1 group, comprising the US, UK, France, China, Russia and Germany. All the countries except Russia and China have sent their highest-ranking foreign envoys.