Oil prices, a key catalyst for the Gulf's financial markets, extended their rally as investor appetite improved amid a growing view that the Omicron coronavirus variant may not cause severe illness and will likely have a limited impact on global fuel demand.

Saudi Arabia's benchmark index (.TASI) gained 0.8%, buoyed by a 1% rise in Al Rajhi Bank (1120.SE) and a 1.3% increase in petrochemical maker Saudi Basic Industries Corp (2010.SE).

The kingdom said on Sunday it expected to post its first budget surplus in nearly a decade next year, as it plans to restrict public spending despite a surge in oil prices that helped to refill state coffers hammered by the pandemic.

Riyadh plans to reduce military spending next year by around 10% from its 2021 estimates, the budget showed, a sign that the cost of the military conflict in neighbouring Yemen has started to ease.

Dubai's main share index (.DFMGI) added 0.4%, with blue-chip developer Emaar Properties (EMAR.DU) rising 1% and sharia-compliant lender Dubai Islamic Bank (DISB.DU) climbing 0.7%.

Dubai's deputy ruler and finance minister Sheikh Maktoum Bin Mohammed announced the listing of Emirates Central Cooling Systems Corporation (Empower), the emirate's media office reported on Saturday.

Gulf exchanges are likely to have another busy year of initial public offerings (IPOs) in 2022, possibly surpassing this year's bumper crop, Reuters reported on Sunday, citing a Bank of America (BAC.N) executive.

In Abu Dhabi, the index (.ADI) lost 0.3%, with the country's largest lender First Abu Dhabi Bank (FAB.AD) dropping 2.1%.

The Qatari index (.QSI) eased 0.2%, hit by a 1.5% decline in the Gulf's biggest lender Qatar National Bank (QNBK.QA).