Saudi Aramco is considering shelving plans for an international public offering in favor of a private share sale to the world’s biggest sovereign wealth funds and institutional investors.

Talks about a private sale to foreign governments—including China—and other investors have gathered pace in recent weeks, according to five people familiar with the IPO preparations, amid growing concerns about the feasibility of an international listing.

The Saudi state oil company has struggled to select a suitable international venue for its shares, as New York and London have vied for what has been billed as the largest ever flotation.

The company would still aim to list shares on the kingdom’s Tadawul exchange next year if they pursue the private sale, the people said. No final decision has yet been made and an international listing could still occur next year.

If Saudi Aramco pursues the private share sale option, an international listing could also follow, but would likely not be until 2019 or later.

The latest proposal by the company’s financial advisers was described by one of the people as a “face-saving” option for Saudi Aramco, which has worked on plans to list its shares internationally for more than a year.

One person working for Saudi Aramco said that the Chinese government is close to playing a key role in any new plan.

Doubts among advisers and the country’s highest authorities have grown about listing on an international exchange. Saudi Aramco’s internal operations and finances have been shrouded in secrecy for decades and its close relationship with the state has thrown up numerous financial, legal and regulatory challenges.

A Saudi Aramco spokesperson said: “A range of options, for the public listing of Saudi Aramco, continue to be held under active review. No decision has been made and the IPO process remains on track.”

The planned listing of a 5% stake in Saudi Aramco is the centerpiece of an economic reform program led by Saudi Arabia’s powerful crown prince Mohammed bin Salman, who is keen for a 2018 IPO. He has said the company could be worth $2 trillion although a Financial Times analysis put the valuation figure at around $1 trillion.

An economic recession in the kingdom is piling pressure on the prince, the king’s son and next in line for the throne, amid calls for the government to increase investment and ease austerity.

A person familiar with Saudi Aramco’s IPO preparations said while there is not an active push to “abandon” the international listing, it could be delayed beyond 2018, to 2019 or later. He said by not pursuing a London or New York listing the company would risk forgoing the deepest pools of international capital.

Another person said a combined private placement and domestic listing, which would be easier to execute, would boost the company’s valuation and bolster the development of the Saudi market.

Some financial advisers to the company, the backbone of the kingdom’s economy, are increasingly concerned that Saudi Arabia could forgo an international listing altogether, according to one of the people involved in the talks.

The Saudi royal family is concerned about legal risks arising from a New York listing, including new U.S. terrorism legislation that allows families of the victims of the 9/11 terror attacks to sue Saudi Arabia, the person said.

It is also worried that a UK listing would put them under more scrutiny than the company is used to, the person added. The UK’s Treasury select committee is preparing to grill its financial regulator over whether it watered down rules to allow Saudi Aramco to list in London.

Should the company pursue a private share sale it plans to engage with sovereign wealth funds as well as institutional investors, said a Saudi official, adding the country did not want to “restrict itself.”

It is unclear if this new proposal is backed by Prince Mohammed and there is no guarantee it will go ahead. One banker close to Aramco said this option could also generate new problems, given the size of the potential Aramco listing compared with the $460 billion market capitalization of the Tadawul market in Riyadh.

For advisers working on the IPO, delaying the listing buys them more time to solve the more complex problems, said a person familiar with the matter, for example around disclosure requirements, antitrust rules or listing requirements.

There has been growing discord within Aramco ranks about the benefits of a listing for the country. Four people close to the company have said the government would never be able to generate the same rate of returns by deploying IPO proceeds to non-oil investments.

The emergence of this proposal comes as IPO preparations have faced major delays. Prince Mohammed, who is ultimately in charge of the country’s oil sector, was expected to make a final decision on an international listing venue in June, according to an internal timetable.

Even so, Saudi Aramco’s CEO Amin Nasser said earlier this month that the IPO remained on track for 2018.