China has said that it remains committed to Iran's nuclear deal with world powers and assured Tehran that it will continue buying nearly one-third of Iranian oil exports.

But while China on May 9 became the last of the world powers that signed the 2015 agreement to say it will honor the pact despite the U.S. decision to withdraw, Iranian rival Saudi Arabia said that it will support the U.S. withdrawal by making up for any shortfall in Iran's oil production caused by renewed U.S. sanctions on Iran.

"We express regret over this decision made by the United States," Chinese Foreign Ministry spokesman Geng Shuang said. He said that China wanted to "ensure the integrity and sanctity" of a pact that Beijing believes was important for curbing nuclear proliferation and promoting stability in the Middle East.

Geng said that China, which has for years been a close economic partner with Iran, will "carry on the normal and transparent pragmatic cooperation with Iran on the basis of not violating our international obligation."

China's Xinhua news agency also reported on May 9 that China's special envoy for the Middle East, Gong Xiaosheng, said after meeting with Iranian officials that the multilateral deal was "very serious and important."

"Having a deal is better than no deal. Dialogue is better than confrontation," he said.

China buys the largest share of Iranian oil, and most of the rest is sold to the other top Asian consumers, Japan and South Korea, which have also indicated that they will continue business with Iran despite the U.S. decision.

China's comments came as oil prices hit their highest levels since November 2014 in world markets as investors reacted to U.S. President Donald Trump's move to withdraw from the pact. Premium crude prices ended over $77 a barrel in London trading on May 9.

The renewed U.S. sanctions are expected to hit Iran's oil sector hard, with analysts estimating Iran's nearly 4 million barrels of daily oil production could be cut by 200,000 barrels to 600,000 barrels a day.

U.S. officials in announcing the renewed sanctions said they expected U.S. allies in the oil-rich Persian Gulf region to make up Iran's shortfall in production, in a move they said would soften the impact of the sanctions on global oil prices.

Saudi Arabia, Iran's fiercest rival in the Arab world and a longtime opponent of the nuclear agreement, stepped forward on May 9 to say it will offset the loss of Iranian crude, saying it "remains committed to supporting the stability of oil markets."

That commitment by the world's largest oil producer may help to temper oil-price increases, but analysts said it is certain to be challenged by Iran and other members of the Organization of the Petroleum Exporting Countries as a violation of the cartel's current limits on oil production.

With reporting by AP, AFP, and Reuters

