He is also on the board of Qatar Investment Authority, the country's sovereign wealth fund.

While he is not part of the royal ruling class, he comes from an affluent and influential family with large investments in the country, including trade and real estate.

Hussein Ibish, a Washington-based Gulf expert, tweeted on Thursday that it was "pretty remarkable" that Emadi was arrested "on suspicion of corruption and embezzlement".

Qatar-based diplomats told AFP that the arrest had come as a surprise.

"This is actually great, it shows Qatar is taking corruption seriously -- if that is what it is found to be -- and helps build the image of the rule of law being complied with,"' a diplomat in Doha told AFP.

Troubled times

Emadi stewarded the economy through a three-year economic blockade imposed on Qatar by Saudi Arabia, the United Arab Emirates, Bahrain and Egypt over allegations it was too close to Iran and funded extremists. Doha has always denied the accusations.

He won accolades for not allowing the currency to devalue in the face of extreme external pressure, liquidating almost a quarter of Qatar's economic reserves to weather the storm.

Emadi also presided over massive spending for the 2022 World Cup which Qatar is to host.

Gas-rich Qatar is one of the smallest Arab states, with a population of 2.8 million, most of whom are foreigners.

In June 1995, former emir Sheikh Khalifa bin Hamad Al-Thani was dethroned in a bloodless coup by his son, the father of the current emir, Sheikh Hamad bin Khalifa Al-Thani.

Sheikh Hamad inherited virtually empty state coffers amid swirling allegations of corruption and economic mismanagement by his predecessor.

The current over an annual anti-corruption award for those who have worked to combat graft globally.

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