Recasts headline and first paragraph, updates shares, adds details and background throughout
By Federico Maccioni and Ateeq Shariff
DUBAI/BANGALORE June 15 (Reuters) - Stock markets across the Gulf fell on Sunday morning after Israel and Iran launched fresh attacks on each other overnight, sparking fears of a widening conflict in the Middle East.
Israel said it had targeted Iran's nuclear facilities, ballistic missile factories and military commanders in strikes that started on Friday and continued over the following days, in what it warned would be a prolonged operation to prevent Tehran from building an atomic weapon.
Iran responded by launching attacks on Israel and calling off Sunday's nuclear talks that the United States said were the only way to halt Israel's bombing.
The Qatari stock market index .QSI slid 2.9% by around 0815 GMT, with almost all constituents in negative territory. Among them, Qatar Gas Transport Nakilat QGTS.QA extended losses and was down 3.1%, while Qatar Electricity and Water Company QEWC.QA was down 1.7%.
Qatar National Bank QNBK.QA, the Gulf's biggest lender, retreated 3.3%.
Israel late on Saturday attacked Iranian energy infrastructure, including an offshore installation on the South Pars gas field, which Iran shares with Qatar, and is the source of most of the gas produced in Iran, stoking fears of potential disruption to the region's energy exports.
Saudi Arabia's benchmark index .TASI recovered some ground to trade 1.6% lower, after plunging 3.6% at the open as stocks fell across sectors.
In Kuwait, where the main index .BKP was down 4.3%, shares in Jazeera Airways JAZK.KW fell as much as 10%, as airlines avoided the airspace over most of the region.
Elsewhere in the Gulf and wider Middle East, the Muscat Stock Exchange .MSX30 registered a 1.5% fall, the Bahrain index .BAX eased by 0.8%, while Tel Aviv stocks opened lower by 1.5%.
Oman was a mediator between Iran and the United States in the nuclear talks.
The Dubai .DDFMGI and Abu Dhabi .FTFADGI bourses in the United Arab Emirates, which will reopen on Monday, closed down 1.9% and 1.3%, respectively, on Friday.
(Reporting by Ateeq Shariff in Bengaluru and Federico Maccioni in Dubai; Editing by David Goodman and David Holmes)
((AteeqUr.Shariff@thomsonreuters.com; +918061822788;))

