May 17 (Reuters) - U.S. fund General Atlantic and Canadian pension fund CPPIB are readying a 3 billion euro ($3.26 billion) offer to buy Spain's largest online real estate company Idealista, Spanish newspaper Expansion reported on Friday, citing unidentified market sources.

Swedish private equity fund EQT, which has controlled Idealista since 2020, has hired investment bank Morgan Stanley to sell its stake in a deal that would value the portal at 2.5 billion euros, people familiar with the matter told Reuters in February.

EQT bought a majority stake from Apax Partners and management in 2020, in a deal that valued the company at about 1.3 billion euros.

Founded in 2000, Idealista operates in Spain, Portugal and Italy, and allows real estate agents to advertise their properties in exchange for a recurring subscription fee. It also provides online advertising, mortgage brokerage and data analytics services for real estate agents.

General Atlantic, CPPIB and EQT did not immediately respond to messages seeking comment. An Idealista spokesperson declined to comment.

($1 = 0.9202 euros) (Reporting by Tiago Brandao editing by Inti Landauro; Editing by Kim Coghill)