The United Arab Emirates' senior national security adviser met his Iranian counterpart in a rare visit to Iran on Monday in a diplomatic move aimed at overcoming their long-standing differences and increasing cooperation.

Sheikh Tahnoon bin Zayed Al Nahyan's visit took place days after Tehran and world powers broke off talks in Vienna aimed at salvaging Iran's 2015 nuclear pact, which Washington abandoned three years ago and reimposed harsh sanctions on the country.

Sheikh Tahnoon, who is a brother of the UAE's de facto ruler, Abu Dhabi Crown Prince Mohammed bin Zayed, discussed expanding bilateral ties and regional issues with Iran's top security official Ali Shamkhani, Iran's Nournews reported.

With business ties to Iran stretching back over a century, the emirate of Dubai, 150 kms (100 miles) across the Gulf, has long been one of Iran's main links to the outside world.

However, they have been on different sides in the war in Yemen. The UAE is a key member of the Saudi-led coalition which backs the internationally-recognised government against Houthi fighters.

In 2019, the UAE started engaging with Iran following attacks on tankers off Gulf waters and on Saudi energy infrastructure. Saudi Arabia began direct talks with Iran in April, with Riyadh describing the talks as "cordial" but largely exploratory.

Analysts said Tehran can ill afford to lose Dubai as a trade route, particularly since US sanctions have drastically reduced its oil exports and made doing international business increasingly complicated.

Anwar Gargash, the diplomatic adviser to the UAE president, said last month that the UAE is taking steps to de-escalate tensions with Iran as part of a policy choice towards diplomacy and away from confrontation.