Most major Gulf stock markets fell on Wednesday, with Saudi banking shares pushing that index down the most, amid rising regional geopolitical tensions and ahead of U.S. Federal Reserve events.

Tensions in the Middle East remained in focus after the United States said it would take every action it can to prevent an Iranian tanker sailing in the Mediterranean from delivering oil to Syria in contravention of U.S. sanctions. 

Adding to the tension was Australia agreeing to join a U.S.-led mission to protect Gulf shipping. Iran denounces the effort and insists countries in the region can protect waterways and work towards signing a non-aggression pact. 

Elsewhere, focus also shifted to the minutes of the U.S. Federal Reserve's most recent meeting, due on Wednesday, given the currencies of Saudi Arabia, the United Arab Emirates and Qatar are pegged to the U.S. dollar. 

In Saudi Arabia the index closed 0.9% lower with Al Rajhi Bank declining 1.3% and Riyad Bank losing 1.5%.

The Middle East's largest index was also hit by disappointment over some corporate earnings. Tabuk Agricultural Development  lost 5.3% after it swung to a second-quarter loss, while Saudi Fisheries shed 1.5% as its losses widened in the same period.

Saudi Arabia's largest food products company, Savola Group, closed 2.5% down after it reported a 21.7% decrease in second-quarter profit. 

Walaa Cooperative Insurance, which is in merger talks with Metlife AIG ANB, shed 2% after EFG Hermes cut its target price to 11 riyals from 20.8 riyals. 

In Abu Dhabi, the index dropped 0.6% with the United Arab Emirates' largest lender First Abu Dhabi Bank FAB.AD slipping 0.4%.

Gulf Pharmaceutical Industries (Julphar) lost a further 7% a day after it plunged 9.8%. On Tuesday, the firm said that it recalled a single batch of its Laxocodyl suppository over a labelling error. 

Egypt's blue-chip index decreased 0.5%, led by a 0.5% fall in its largest lender Commercial International Bank.

Emaar Misr plunged 5.7% extending its losses from previous session following a lawsuit filed by an Egyptian businessman against the developer claiming part of the land at the Marassi project. 

Qatar's index slid 0.2% snapping a three-session winning streak. Petrochemical maker Industries Qatar dropped 2.3% and Barwa Real Estate lost 1.5%.

The index has been benefiting since the central bank said last week Qatari economic growth would accelerate over the next two years amid expectations of stable oil prices and continued strong exports. 

Dubai's index edged up 0.1% as Emirates NBD gained 1.3% and Emirates Integrated Telecommunications increased 1.8%.

(Reporting by Maqsood Alam in Bengaluru Editing by Frances Kerry) ((Maqsood.Alam@thomsonreuters.com;))