Most Gulf equities rose in early trade on Monday after the US and Iran announced a preliminary deal to end the war and restore traffic through the Strait of Hormuz.
Pakistan's prime minister said the two countries are expected to sign a memorandum of understanding in Switzerland on Friday, following mediation by Islamabad.
Trump said on Sunday the waterway would reopen "toll free" and that the US blockade of Iranian ports would be lifted, while Iran's Mehr news agency reported the draft deal envisages reopening it within 30 days under Iranian arrangements.
Saudi Arabia's benchmark index gained 0.5%, with the country's biggest lender by assets, Saudi National Bank.
However, oil giant Saudi Aramco slipped 1.1%.
Brent crude futures fell $3.65, or 4.2%, to $83.68 a barrel by 0630 GMT.
Qatar's benchmark index advanced 1%, with Qatar National Bank, the region's largest lender, jumped 1.9%.
UAE bourses were closed for a public holiday.
