Castlelake has confirmed it is in the early stages of considering an offer for the carrier, but stressed no approach has been made.
EasyJet, meanwhile, said Castlelake's interest comes while its share price is "temporarily depressed" owing to the effects of the war in Iran.
"The board of easyJet has not had any discussions with, nor received any approach or proposal from Castlelake," it said in a statement issued on Monday morning (1 June).
For its part, Castlelake added: "There can be no certainty that any offer will be made, nor as to the terms of any offer."
EasyJet's share price was up by just under 1% when the London Stock Exchange opened on Monday morning to £3.98.
The carrier's board stressed its duty was to consider any proposals should there by one made and to maximise value for shareholders.
On any potential valuation, easyJet said: "The board notes the highly opportunistic timing when easyJet’s share price is temporarily depressed due to the current situation in the Middle East and its impact on customer confidence and jet fuel prices."
While on deliverability, it added: "The board notes the considerable regulatory, financial and other execution challenges associated with a potential takeover of easyJet."
EasyJet's board stressed too there was no imperative to sell. "EasyJet is in a position of strength, underpinned by an investment grade balance sheet with a net cash position, alongside strong customer satisfaction and high employee engagement.
"The board remains highly confident in easyJet’s strategy and its ability to deliver attractive long-term value for shareholders. The company remains focused on executing its medium-term target of delivering greater than £1 billion profit before tax."
Shareholders have been advised not to take any action, and easyJet has said a further announcement will be made "as and when appropriate".
Last month, easyJet recorded a deeper first half (six months to the end of March 2025) headline loss before tax of £552 million, an increase from £394 million compared with the same period a year earlier.
This was partially offset by the continued strong performance of easyJet holidays, which delivered a first half headline profit of £61 million following a more than £100 million increase in revenue from £400 million to £518 million off the back of a 22% increase in passengers.
