EasyJet has rejoined the FTSE 100, but its return could be short-lived after the company agreed to be bought by a private equity firm in a £5.7 billion deal.

The latest quarterly reshuffle was confirmed after the stock markets closed on Wednesday.

EayJet’s return comes six months after it was demoted to the lower ranks of the FTSE 250.

The budget airline had seen its share price decline after reporting widening losses on its balance sheet.

But it has been given a boost in recent months after becoming the subject of a bidding battle between investment firms Apollo and Castlelake.

Castlelake walked away from talks last month after Apollo put down a higher offer to pay shareholders 715p per share for the business, valuing easyJet’s fully diluted share capital at about £5.7 billion.

EasyJet shares have jumped by about 30% since the start of the year.

The takeover, which will require approval from shareholders, regulators and the court, is expected to complete in the first quarter of 2027.

This would mean being taken off the London Stock Exchange and into private ownership.

Richard Hunter, head of markets for Interactive Investor, said easyJet’s promotion to the FTSE 100 marks a “last hurrah”.

“The company, which has flitted in and out of the premier index during its history, will at least be ending on a high,” he said.

“Less well known is Ithaca Energy, a British oil and gas company which operates in the North Sea.

“A subsidiary of Israeli Delek Group, the company has seen its shares rise by 64% so far this year since its growth pipeline includes a 20% interest in the Rosebank field, which is subject to regulatory approval for first oil in the first half of 2027.

“Improved guidance and a generous 9.7% dividend yield add to the investment case.”

Meanwhile, Ladbrokes and Coral owner Entain has slipped down to the FTSE 250 after its share price has weakened by about 30% since the start of the year, despite beating expectations for its first half financial performance.

But the group said it is set to be hammered by new UK gambling taxes worth about £250 million.

Persimmon has also faced relegation after seeing its share price sink by about 16% this year.

The company has reported coming up against challenging conditions in the housing market, with mortgage rates spiking in the spring following the escalation of conflict in the Middle East.