The group, called Planet IB, said it intended to offer 13.50 Egyptian pounds ($2.23) per share to buy the Cairo-based investment bank, Egypt's biggest. Shares in EFG closed at 10.99 pounds on Thursday, the last day of Egypt's trading week.

EFG shareholders voted to go ahead with an earlier plan to form a joint venture with Qatar's QInvest that would give the Qatari firm control over EFG's main business, Planet's chairman, Mahmoud Abdel Latif, told Reuters.

Alongside Abdel Latif, until recently chairman of Cairo-based AlexBank, Planet's investors include Egyptian billionaire Naguib Sawiris and the son of the ruler of the Gulf emirate of Sharjah, Tariq bin Faisal al-Qassimi.

Abdel Latif said the EFG board had railroaded rejection of the offer through the meeting at a time when many of the shareholders were out of the room watching the verdict being read in the trial of Egypt's ousted leader, Hosni Mubarak.

"Around 50 percent were there, and these 50 percent were mostly people who were directed by the management to attend," Abdel Latif said. Before the vote, "some of the 50 percent who were in the meeting went outside into the lobby of the hotel to watch TV and listen to the Mubarak verdict."

Neither of EFG's two chief executives was answering the phones.

Planet was asking the regulator to halt the process and have another vote taken after shareholders were allowed to hear Planet IB's offer, Abdel Latif said.

"I think that is fair to everybody," he said.

"Our legal argument is the process in the general assembly was not really transparent and did not give people time to think, and that the board of directors directed the shareholders who attended to take a decision against Planet IB's offer."

He said his group had sent a letter to the regulator and planned to meet with Egyptian Prime Minister Kamal al-Ganzouri on Sunday to gain support for its buyout offer.

Planet had earlier lined up investors and then asked EFG to give it a short amount of time to perform due diligence on the bank before making a tender offer on the Egyptian stock exchange, Abdel-Latif said.

EFG's market value has more than halved to less than $870 million since the national uprising that ousted Mabarak last year. The joint venture with QInvest would give the Qatari firm control over EFG's main business.

Sawiris, one of Egypt's richest men, built a global telecoms empire by venturing into frontier markets with strong growth potential.

Now 57, he has eased off day-to-day management of his empire after selling assets including Italian operator Wind and his most lucrative business, Algeria's Djezzy, to Russia's Vimpelcom (VIP.N) in a deal worth $6 billion.

EFG has securities brokerage, investment banking, asset management, research and private equity operations and a controlling interest in Lebanese lender Credit Libanais.

Egyptian share prices have tumbled since Mubarak's ouster, and many investors have been looking to snap up assets seen as undervalued.

The bank came under further pressure on Wednesday, when its two chief executives, Hassan Heikal and Yasser El Mallawany, were referred to trial alongside Mubarak's two sons as part of a probe into illegal share dealings. EFG said it would defend the two CEOs.

(Writing by Patrick Werr and Edmund Blair; Editing by Robin Pomeroy and Peter Cooney)

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