DUBAI: Qatar's stock market was trading down early on Sunday as shares of Commercial Bank fell after talks to sell its stake in United Arab Bank UAB.AD to a UAE investor failed.

Saudi Arabia's index was also down, while Dubai showed some gains after the emirate's government announced new measures to stimulate the economy.

Qatar's index shed 0.6 percent with Commercial Bank falling 1.9 percent after announcing talks with Tabarak had ended without a deal following months of negotiations. United Arab bank was flat on the Abu Dhabi index.

Commercial Bank started talks to sell its stake in United Arab Emirates-based (UAE) United Arab Bank to Tabarak last year.

Qatar has been embroiled in a political row with the United Arab Emirates UAE, Saudi Arabia, Bahrain and Egypt for over a year.

Blue chip Industries Qatar was down 1.5 percent.

In Saudi Arabia, the index fell 0.4 percent as top petrochemical company Saudi Basic Industries shed 1.3 percent. Al Marai, the Gulf's largest dairy company, was down 2.3 percent.

Shares in National Medical Care Co jumped 7.5 pct in early trade to 60 Saudi riyals ($16.00) after the company said a unit of General Organization for Social Insurance (GOSI) reached a non-binding agreement with NMC Health to enter a private sale transaction. The shares will be swapped at 70 riyals. 

Dubai's index showed modest gains after state news agency WAM reported on Saturday the government of Dubai would make it easier for companies to clear corporate fines and renew their licence.

Dubai has announced a series of initiatives to reduce corporate costs and stimulate growth, but it remains unclear whether the steps can revitalise a slumping real estate market, a core sector of the emirate's economy.

Builder Arabtec rising 3.1 percent after gaining 4.3 percent on Thursday. It has rebounded sharply from a multi-year low since it reported in mid-May its highest quarterly profit since late 2014.

(Reporting by Alexander Cornwell; Editing by Elaine Hardcastle) ((Alexander.Cornwell@thomsonreuters.com;))