* To buy 51.3 percent controlling stake
* Closing seen within 3 months
* Partner, Scailex shares fall
(Adds details, share reaction, background))
JERUSALEM, Aug 12 (Reuters) - Scailex Corp said on Wednesday it had signed a deal to buy Hutchison Telecommunications stake in Israeli mobile phone operator Partner Communications for $1.38 billion.
Scailex, which imports mobile phones mainly from Samsung Electronics, said in a statement to the Tel Aviv Stock Exchange it will buy 78.94 million shares of Partner, or a 51.31 percent stake, at $17.50 a share.
Partner's Nasdaq-listed shares closed at $17.21 on Tuesday.
Partner, Israel's second largest mobile phone provider, operates under the Orange brand name.
Its Tel Aviv shares had been suspended pending the annoucement. When they opened, they were down 0.9 percent. Scailex's shares were down 3.5 percent in early trade.
Scailex said the deal was subject to a number regulatory and other approvals but that it expected closing within three months.
Hong Kong conglomerate Hutchison Whampoa, which controls Hutchison Telecommunications, said last month it wanted to sell its majority stake in Partner, whose market value is 10.3 billion shekels ($2.7 billion).
Bids for the Partner stake were due last Wednesday.
Scailex said last month it was in talks with a third party to issue securities to fund a possible purchase. It said should this happen, Suny Electronics Inc, which controls Scailex with an 86.5 percent stake, would lose its majority share. ($1 = 3.88 shekels) (Reporting by Steven Scheer)