Abu Dhabi's state-owned Etihad Airways said it would suspend all flights to and from Doha from Tuesday morning until further notice.

Etihad, which operates four return flights to Doha daily, said the measure will be in place 'until further notice'.

Saudi Arabia, Egypt and the UAE all declared it a 'terrorist group' after a Brotherhood government, led by Mohamed Morsi, won democratic elections in Egypt before being overthrown by the military in 2013.

Qatar is dependent on the UAE and Saudi Arabia for its white sugar imports, which are estimated at less than 100,000 tonnes annually.

The announcement that six countries have severed diplomatic ties could lead to food shortages in Qatar, analysts have warned Six nations have cut ties with Qatar over accusations that the gas-rich country supports terror groups.

Qatar blamed hackers for a string of explosive remarks attributed to its Emir Sheikh Tamim bin Hamad Al-Thani after President Donald Trump visited Saudi Arabia, its giant neighbour.

The reputed remarks were a slap in the face to Riyadh and Abu Dhabi, Sunni monarchies which have embraced Trump and his harder line against Shiite-dominated Iran.

The diplomatic broadside threatens the international prestige of Qatar, which is set to host the 2022 FIFA World Cup.

It has for years presented itself as a mediator and power broker for the region's many disputes.

In March 2014, Saudi Arabia, the United Arab Emirates and Bahrain recalled their ambassadors from Qatar over the rift.

Eight months later, they returned their ambassadors as Qatar forced some Brotherhood members to leave the country and quieted others.

Other carriers from the three Gulf countries are likely to announce similar measures.