Thomas Cook, the world's oldest travel firm, collapsed on Monday, stranding hundreds of thousands of holidaymakers around the globe and sparking the largest peacetime repatriation effort in British history.

The firm runs hotels, resorts, airlines and cruises for 19 million people a year in 16 countries. It currently has 600,000 people abroad, forcing governments and insurance companies to coordinate a huge rescue operation.

In a statement, the company said an agreement on a last-minute rescue could not be reached, despite "considerable efforts."

Chief Executive Peter Fankhauser called the collapse "a deeply sad day for the company," describing the firm as a pioneer of package holidays which "made travel possible for millions of people around the world."

The UK's Civil Aviation Authority said Thomas Cook had now ceased trading and it would work with the government to bring the more than 150,000 British customers home over the next two weeks.

The operator said Friday that it needed 200 million British pounds (250 million U.S. dollars) – in addition to the 900-million British pounds rescue deal secured last month – or else it would face administration.

Chinese conglomerate Fosun, which was already the biggest shareholder in Thomas Cook, agreed last month to inject 450 million British pounds into the business.

In return, the Hong Kong-listed group acquired a 75 percent stake in Thomas Cook's tour operating division and 25 percent of its airline unit.

Creditors and banks agreed to inject another 450 million British pounds under the recapitalization plan announced in August, converting their debt in exchange for a 75 percent stake in the airline and 25 percent of the tour operating unit.

Thomas Cook in May revealed that first-half losses widened on a major write-down, caused in part by Brexit uncertainty that delayed summer holiday bookings. The group, which has around 600 stores across the UK, has also come under pressure from fierce online competition.

Thomas Cook's overall revenue from its package tour business in 2018 was 7.4 billion pounds (9.3 billion U.S. dollars,) a fall of 88 million pounds from the previous year.

Fosun, which also owns Premier League football team Wolverhampton Wanderers, has held 18 percent in Thomas Cook since 2015, and in 2016 the two companies launched a joint venture in China, focusing on the country's domestic travel market.

According to China Daily, in the past year, Thomas Cook China has launched five hotels in the country. Talking to Chinese media earlier this year, head of Thomas Cook China Allesandro Dassi said that the venture would focus on family-oriented travel, geared towards parents and children.

It remains uncertain what the collapse of Thomas Cook and its UK entities will mean for the Chinese joint venture. At the time of writing, Thomas Cook China's website was still active, unlike its British counterpart.

(With inputs from Reuters, AFP)