Qatar's stock market surged to its biggest intra-day high in nine months on Thursday after report that Qatar's prime minister will attend an Arab summit in Saudi Arabia, while all major Gulf bourses also rallied mostly riding on financial stocks.

Qatar's prime minister will attend an Arab summit in Saudi Arabia on Thursday to discuss regional security, the Foreign Ministry said on Wednesday, the highest level Qatari official to visit the kingdom during a diplomatic rift.

Saudi Arabia, the United Arab Emirates, Bahrain and Egypt imposed an economic and diplomatic boycott on Qatar in June 2017 over allegations that Doha supports terrorism, a charge Qatar denies.

Qatar's index rose 3.4% to hit its sharpest intra-day high since August 2018. Banks led the gains with Qatar National Bank  leaping 4.4% and Commercial Bank soaring 9%.

"Euphoria in Qatar today is on the back of a report that the PM will attend the Gulf summit over the weekend - this is the most senior official to go to the Kingdom since the embargo in 2017," said Vrajesh Bhandari, senior portfolio manager at Al Mal Capital.

"Another factor is the stock split, that is change in par value from QAR 10 to 1, which local retail investors see as a catalyst."

A 10-to-one stock split for companies on the exchange will be phased in from June 9, aiming to encourage small investors to invest to increase liquidity.

The Abu Dhabi index climbed 2.8%, rising for the fourth straight session. First Abu Dhabi Bank, the United Arab Emirates' largest lender, jumped 4.1% to 14.9 dirhams, while Emirates Telecommunications Group was up 4.5%.

First Abu Dhabi Bank shares touched a record 17 dirhams late last month following a foreign ownership limit increase to 40% from 25%.

But the stock has seen cooling since then, under pressure from the global trade dispute and geopolitical worries, and as MSCI retained its foreign inclusion factor at 25%, disregarding the foreign ownership limit rise.

The session's rise has sent the index back into positive territory this year after a sell-off earlier in May had turned the index red.

Saudi's index was up 1.2% a day after joining MSCI's emerging market index. Banks and petrochemical shares were the biggest boost, led by Riyad Bank, which climbed 3.1% and petrochemical maker Saudi Basic Industries, which traded 1.6% up.

Sahara International Petrochemical gained 4.2% after on Wednesday it appointed Saleh Muhammed Bahamdan its chief executive.

In Dubai, the index closed 0.8% higher, boosted by financial and real estate shares with its largest listed developer, Emaar Properties, adding 1.4% and the biggest lender Emirate's NBD, gaining 0.9%.

Outside the Gulf, Egypt's blue-chip index closed 1.4% lower as 28 of its 30 stocks declined. Real estate shares were the biggest drag with real estate investment firm Talaat Mostafa Group Holding shedding 4.5%.

Global Telecom dropped 5.3%. It said on Thursday the firm was in discussions with the Egyptian Tax Authority on certain tax claims.

(Reporting by Ateeq Shariff in Bengaluru Editing by Frances Kerry) ((; +918067497129;))