All major Gulf markets rose for a third straight session on Monday, boosted by financial stocks amid rising oil prices, while Saudi Arabia and Qatar gained sharply as most of their banks increased.

Oil prices rose by 2 percent on Monday, extending a rally from December's 18-month lows with support from OPEC production cuts and steadying share markets. 

Saudi Arabia's index rose 1.5 percent to close at its highest since Aug. 12, 2018, with 11 of its 12 banks gaining.

Saudi Arabia is due to join the emerging market indexes of MSCI and FTSE Russell this year, which is expected to attract $15 billion of passive, index-linked funds and billions more in active funds.

As a result, Saudi Arabia was the favourite market of fund managers polled by Reuters late last month, with 54 percent expecting to raise their Saudi equity allocations and none to reduce them in the next three months.

Saudi exchange data released late on Sunday showed that foreigners were net buyers of 134.3 million riyals ($35.80 million) of stocks last week.

Al Rajhi Bank , the kingdom's second-largest lender by assets, rose 2.2 percent to trade at nearly 11-year high; the stock had gained over 5 percent in the last session on plans to increase its capital to 25 billion riyals from 16.25 billion riyals.

Bank Aljazira 1020.SE added 2.7 percent after proposing a dividend of 0.5 riyal per share for year 2018, up from 0.3 riyal per share a year earlier.

The petrochemical sector was mixed, however, with Saudi’s largest petrochemical maker gaining 1 percent. But Saudi Arabian Fertilizers dropped 2 percent; earlier this week, it announced a planned shutdown of its plant for 117 days which, the firm said, will cost an estimated 121 million riyals.

Qatar's index gained 1.4 percent with six of its 7 banks increasing.

Qatar Commercial Bank jumped 4.1 percent while market heavyweight Industries Qatar  added 2.9 percent.

In Abu Dhabi, the United Arab Emirates' largest lender First Abu Dhabi Bank climbed 1 percent, which helped the index  rise 0.6 percent.

The Dubai index edged up 0.1 percent with the emirate’s largest lender, Emirates NBD, gaining 2.1 percent.

Egypt market was closed on Monday for a public holiday.

($1 = 3.7509 riyals)

SAUDI ARABIA The index rose 1.5 pct at 8,048 points DUBAI The index was up 0.1 pct to 2,535 points QATAR The index rose 1.4 pct to 10,494 points ABU DHABI The index added 0.6 pct to 4,934 points KUWAIT The index was up 0.5 pct at 5,403 points OMAN The index  gained 0.2 pct to 4,312 points BAHRAIN The index was flat at 1,331 points

(Reporting by Shakeel Ahmad and Ateeq Shariff in Bengaluru; Editing by Alison Williams) ((;))