Kharafi, a major Zain shareholder, is expected to send an official acceptance to Etisalat's offer, a source familiar with the matter told Reuters on Thursday.
Etisalat has offered 1.7 Kuwait dinars per share for a 46 percent stake in Zain.
Trading in Zain shares, halted on Thursday pending details, will resume on Sunday. The stock had risen to a four-month high on Wednesday, at 1.36 dinars.
National Investment Co, majority-owned by Kharafi group, rose 6.7 percent. After market hours, the firm said that one of its portfolio clients, Al-Khair, had received an offer to sell a stake in Zain.
"Investors are looking to take advantage of where they can make a quick buck," said a Kuwait trader who asked not to be identified. "They see it's good to buy the smaller Kharafi companies because they are easier to move up than a heavyweight like Zain."
Kuwait's index climbed 0.8 percent to its highest finish since May 24. Kuwait stocks typically rally at the quarter end as investors try to boost the value of their portfolios.
Etisalat slipped 0.5 percent on the Abu Dhabi bourse.
"There is speculation that Etisalat is over-paying, but I don't think it will have a big impact on its stock," said Robert McKinnon, ASAS Capital chief investment officer.
Egypt's Orascom Telecom fell 3.6 percent after receiving a new Algerian tax demand of about $230 million. Dubai's Emaar Properties fell 1.8 percent, trimming its September gains to 14.4 percent, after saying it would issue $450 million in convertible bonds.
"Emaar is diversifying its funding, extending the maturity of debt and lowering these funding costs," said Zahed Chowdhury, cash equity sales at Al Mal Capital.
ASAS's McKinnon said the bond issue would be dilutive to existing shareholders.
"But there's a lot of appetite for the offering and 18 months ago there's no way Emaar could have placed this in the market," he added. "The real estate market isn't fabulous but the fact Emaar can now do this is very positive and it's an attractively priced convertible."
Qatar Telecom (Qtel) rose 0.3 percent, with investors little moved by the firms' plan to launch a benchmark US dollar bond.
"The environment has changed to where it was a year and half ago," said Irfan Ellam, vice president for equity research at Al Mal Capital. "Now a bond can be raised with a lower coupon."
Dubai’s index drops 1.1 percent to 1,684 points. In Abu Dhabi, the measure slipped 0.2 percent to 2,673 points. The Kuwaiti index climbed 0.8 percent to 6,985 points, while in Qatar the benchmark fell 0.3 percent to 7,695 points.
Omani index dropped 0.3 percent to 6,473 points. Bahraini index rose 0.09 percent to 1,445 points.
