Expect plenty of jockeying between Iran and Saudi Arabia for favor with China when President Xi Jinping travels to the volatile region on Tuesday.

The countries are among the world’s biggest oil producers. Both desperately need to raise crude exports to help stave off the effects of lower global prices. China, as one of the globe’s largest oil consumers, is a prime destination.

Mr. Xi’s visit to the region—which along with Saudi Arabia and Iran includes a stop in Egypt before concluding on Saturday—comes at an opportune time if China’s shopping for energy.

The lifting of U.S. sanctions against Iran over the weekend could over time bring a flood of new supply to global markets and potentially further drive down prices. Iranian officials said Sunday the country was preparing to raise production by 500,000 barrels per day.

Together, Iran and Saudi Arabia accounted for nearly one-quarter of China’s total crude imports in the first 11 months of 2015, the latest data available. Analysts say whether Iran can chip away at Saudi Arabia’s position as China’s top crude supplier depends on how far Tehran is willing to go to undercut Riyadh on prices.