DUBAI  - Blue-chip shares helped drive up Dubai stocks on Wednesday, while the Saudi exchange was in negative territory in early trade.

Most Gulf markets opened higher backed by rising oil prices, pushed up by looming U.S. sanctions against Iran which threaten to cut supplies to an already tight market despite pledges by producer cartel OPEC to raise output to make up for the disruptions. 

Emaar Properties opened 1.4 percent higher on the Dubai index, while Dubai Islamic Bank and Emirates NBD were up 0.8 percent and 1.0 percent, respectively.

Contractor Drake & Scull International gained 4 percent, reversing some losses after sinking 9.9 percent on Tuesday.

DSI, one of the worst performing stocks on the Dubai index, has been lagging as a result of concerns about its financial position, business outlook and the outcome of a probe into "violations" by previous management.

The Dubai index was higher by 0.9 percent.

In Saudi Arabia, Fawaz Abdulaziz Alhokair Co dropped 2.7 percent after its Chief Financial Officer Mohammed Abbaoui was quoted by financial news website Argaam on Tuesday as saying that the retailer would close up to 75 loss-making stores this year.

Al Rajhi Bank was down 0.7 percent and Saudi Basic Industries was 0.2 percent lower.

Both are among the largest names on the index and have been among the main beneficiaries of a huge inflow of foreign investment in recent months in anticipation of the bourse's upgrade to emerging markets status.

The Saudi index was down 0.2 percent

In Abu Dhabi, the index opened up 0.5 percent and the Qatar index was also up 0.2 percent.

(Reporting by Alexander Cornwell Editing by Keith Weir) ((Alexander.Cornwell@thomsonreuters.com))