MIDEAST STOCKS-Gulf bourses slide as Hormuz tensions and houthi strikes rattle traders

By Ateeq Shariff

Nov 15 (Reuters) - Most Gulf bourses closed lower on Sunday, with traders weighing the disruption in the Strait of Hormuz alongside Iran-aligned Houthi attacks on Saudi Arabia.

The Iranian navy has confirmed that a Saturday mine strike in the Strait of Hormuz set three oil tankers ablaze, state media reported.

Saudi Arabia's benchmark index .TASI dropped 0.7%, with the country's biggest lender by assets Saudi National Bank 1180.SE losing 2.3%.

On Sunday, the Saudi-led coalition confronting the Iran-backed Houthis announced that it had downed two ballistic missiles fired at the capital, Riyadh, along with three drones over the kingdom's oil-rich Eastern Province.

Houthi strikes on Saudi airports, seaports, and energy installations have intensified, and Riyadh has responded by expanding its air campaign against Houthi targets in Yemen.

In Qatar, the index .QSI retreated 1.8%, as all its constituents were in negative territory including the Gulf's biggest lender Qatar National Bank QNBK.QA, which was down 2.3%.

Amid the fallout from the Iran war, Qatar's LNG exports took a heavy hit when an Iranian attack in March forced Qatar to declare force majeure on deliveries.

Now a long-standing Gulf LNG contract has been cancelled on that basis, a first since the conflict began, and analysts say Poland's Orlen PKN.WA could save up to $2 billion.

Meanwhile, Turkey and Qatar sealed a mutual defence pact on Friday to bolster joint security across the region. In a joint statement following their leaders' talks, they pledged a united front against any foreign armed attack on either country.

Outside the Gulf, Egypt's blue-chip index .EGX30 inched 0.3% higher.