Iran nuclear talks
John Kerry lands in Vienna to iron out 'deep differences' in Iran nuclear talksReuters

The US Secretary of State John Kerry has landed in Austrian capital Vienna to iron out the deepening differences between the delegates of Tehran and world powers.

As the marathon negotiations are racing against the 20-July deadline, Kerry has arrived in Vienna following his successful diplomatic efforts in Afghanistan over disputed presidential election results.

The top American diplomat "will see if progress can be made on the issues where significant gaps remain and assess Iran's willingness to make a set of critical choices at the negotiating table," said a State Department spokesperson.

Iran is currently holding a series of talks with P5+1 powers comprising the US, the UK, China, Russia, France, and Germany.

Kerry is in Vienna at a time when Iran is threatening to walk out of the deal citing "excessive" demands by the Western powers to curb Tehran's nuclear ambitions.

"If we see the excessive demands [from West] persisting and that a deal is impossible, this is not drama, we will continue with our nuclear program," said Iran's chief negotiator Abbas Araqchi, who also expressed hopes that Kerry's presence will resolve "deep differences".

As there are only eight days for the deadline to end the decades-long standoff analysts are also expecting an extension in view of securing a permanent deal.

On the sidelines of the talks, Kerry will also meet his German counterpart Frank-Walter Steinmeier to discuss recent spying allegations.

Berlin has recently asked the CIA station chief to leave the country over snooping charges.

In addition to that, the French delegation has also expressed hopes of discussing the ongoing Israel-Gaza conflict.