The first wave of a massive exercise to bring home hundreds of thousands of Indians stuck abroad was due to begin Thursday with two flights from the United Arab Emirates.

India banned all incoming international flights in late March as it imposed one of the world's strictest virus lockdowns, leaving vast numbers of workers and students stranded.

Some 15,000 nationals will be repatriated from 12 countries on planes and naval ships, in a mammoth exercise which saw the civil aviation ministry's website crash Wednesday as panicked citizens rushed to register. Two warships have steamed to the Maldives and another to the UAE -- home to a 3.3-million-strong Indian community which makes up some 30 percent of the Gulf state's population.

The consulate in Dubai said that it alone had received almost 200,000 applications, appealing on Twitter for "patience and cooperation" as India undertakes the "massive task" of repatriation. The oil-rich Gulf is reliant on the cheap labour of millions of foreigners -- mostly from India, Pakistan, Nepal and Sri Lanka -- many of whom live in squalid camps far from the region's showy skyscrapers and malls.

But coronavirus and the devastating economic impact of the pandemic has left many workers sick and others unemployed, unpaid and at the mercy of sometimes unscrupulous employers.

Delays and frustration

The first two flights from Abu Dhabi and Dubai on Thursday -- both destined for the southern Indian state of Kerala according to an Air India schedule -- will transport just 354 people, and a planned flight from Doha has been postponed until the weekend.

According to Indian media reports, delays in the flight schedule have been triggered by the need to test air crew for coronavirus. A naval vessel is expected to arrive at Dubai's Port Rashid, and the Indian High Commission in the Maldives posted images on Twitter of one of its warships entering Male harbour ahead of Friday's planned evacuation of some 1,000 people.

Other flights will leave Singapore, Malaysia and the Philippines, as well as London in the United Kingdom and San Francisco, New York, Chicago and Washington in the US. But frustrations have boiled over at the slow pace of the exercise, as well as the fact that evacuees will have to pay for their passage home and spend two weeks in quarantine on arrival.

"It is just propaganda," said Ishan, a 35-year-old Indian expatriate in Dubai who hasn't been able to secure a passage home. "Let's say they repatriate 400 people on the first day, and about 5,000 people in 10 days, what difference has it made?"

"We are upset over the failure of our government," said Ishan, who was a manager at a luxury services company before he was made redundant last month. "What about the people with no money? How are you helping them?"

OV Mustafa, the director of Norka Roots, a government welfare body for people from Kerala -- the biggest source of Indians in the Gulf -- said that those abroad were clamouring for permission to leave. "The mood is desperate and panicky. There are limited flights. People have lost their jobs here," he told AFP. "It should have been a massive evacuation."