(Corrects paragraph 12 to say Morningstar is research firm, not brokers)
By Sergio Goncalves and Andrei Khalip
LISBON, Dec 5 (Reuters) - Telecoms group Altice's plan to buy the Portuguese operations of Brazil's Oi for 7.4 billion euros ($9 billion) depends on winning the backing of shareholders in Portugal Telecom SGPS, the holding company which owns 25.6 percent of Oi, a spokesman for Portugal Telecom said.
Lisbon-listed Portugal Telecom SGPS (PT SGPS) is the target of a 1.2 billion-euro ($1.48 billion) takeover offer by Angolan billionaire businesswoman and opponent of the Oi sale, Isabel dos Santos. Her company Terra Peregrin is offering shareholders in PT SGPS 1.35 euros a share on condition that the Altice deal does not go through.
A spokesman for PT SGPS said that the board of Oi is likely to approve the sale of the PT Portugal business to Altice later on Friday.
However, PT SGPS's shareholding in Oi gives it a right of veto over such strategic decisions.
But the spokesman said that since PT SGPS management cannot take strategic decisions due to Portuguese takeover rules, the company will have to call a shareholder meeting "to approve, or not, the sale of PT Portugal".
"The shareholders are sovereign," the spokesman said. "Oi has to present to PT SGPS a justification of the sale of PT Portugal ... come up with arguments for the valuation of the shareholding in Oi, including by PT SGPS," he said.
The approval of the sale will require a two-thirds majority, and that may be hard to muster.
PT SGPS's shares were 1.4 percent lower at 1.39 euros on Friday, valuing the company at 1.25 billion euros ($1.54 billion).
Shares in Oi last traded at 1.31 reais, valuing the company at around $4.2 billion and PT SGPS's stake at around $1.56 billion, according to Thomson Reuters data.
Oi now owns Portugal Telecom's operating assets following a a merger between the two companies, which soured after the now bankrupt Rioforte holding company of the Espirito Santo banking family, ultimately a shareholder in PT SGPS, defaulted on nearly 900 million euros ($1.14 billion) of loans from PT, a debt which Oi said it had not been aware of before their merger deal.
PT SGPS now has no assets aside other than the stake in Oi and the Rioforte debt.
"Whatever happens, I think it's not going to be as clean as Altice, and Oi, would like it to be. With the blocking minority (that PT has in Oi), it's really ugly, in fact," said Allan Nichols, senior analyst at Morningstar research firm.
"Some will prefer to cash out. We don't know how committed the shareholders are to PT's future that depends on Oi. Hedge funds would certainly sell anything to make a buck," he added.
PT SGPS's largest shareholders are Novo Banco, which was carved out from rescued Banco Espirito Santo in August following the collapse of its founding family's business empire, Oi, Portuguese company RS Holding, Norges Bank Investment Management and UBS Global Asset Management.
Novo Banco has a 12.6 percent stake, followed by Oi with 10 percent and RS Holding with 10 percent each. Oi, however, might not be allowed to vote under company rules concerning conflicts of interest. Smaller shareholders with stakes below 3 percent include Portugal's social security fund, Morgan Stanley Investment Management and two Portuguese companies, Visabeira and Controlinveste. ($1 = 0.8137 euros) (Editing by Axel Bugge and Greg Mahlich)