DUBAI, Jan 21 (Reuters) - The chief executive of Saudi Telecom (STC) believes that owning 50 percent of Kuwaiti affiliate Viva would be reasonable, he told Saudi-owned television channel Al Arabiya on Thursday.

The kingdom's leading telecommunications operator holds 26 percent of Viva but announced in November it would launch a voluntary tender offer to acquire up to 100 percent of the Kuwaiti firm.

However, its offer price of 1 dinar ($3.29) per share was dismissed as "not fair" by Viva's board last month. STC still went ahead at the same price with the tender, which is due to close on Jan. 31.

"I think that the total of 50 percent is considered reasonable in Viva," Khaled al-Biyari told the television channel in an interview on the sidelines of the Davos gathering.

STC on Wednesday reported a 20 percent drop in fourth-quarter profit as the benefits of higher revenue were wiped out by rising service costs and expenses.

The Saudi firm's shares were trading 0.9 percent higher at 1005 GMT. Viva's shares closed flat at 0.99 dinars in Kuwait. ($1 = 0.3044 Kuwaiti dinars)

(Reporting by Ali Abdelatti and Hadeel Al Sayegh; Writing by David French; Editing by Keith Weir) ((davidj.french@thomsonreuters.com; +971 4 362 5864; Reuters Messaging: davidj.french.thomsonreuters.com@reuters.net)) <