The White House economic adviser Gary D. Cohn is selling a significant holding in the world’s largest bank — which happens to be in China — as he clears potential conflicts of interest to serve in his new role.

The stock that Mr. Cohn is selling is in the Industrial and Commercial Bank of China, which with nearly $3.5 trillion in assets is the biggest on the planet, and it would be valued at about $16 million based on Thursday’s trading, according to details of his holdings in a set of documents issued by the Office of Government Ethics.

The Chinese bank position appears to be the largest stock, private equity or hedge fund holding — apart from his shares in Goldman Sachs, where he was president — that Mr. Cohn will have to sell because of his new job. The timing of his initial purchase of the Industrial and Commercial Bank shares and of his planned sale are not clear.

Neither Mr. Cohn, who is now the director of the National Economic Council advising President Trump, nor a White House spokeswoman responded to requests for comment. A Goldman spokesman referred questions to the White House.

Mr. Cohn’s holding in the Chinese bank are notable because the Trump administration has portrayed China as a threat to American economic growth.

Relations between the new administration and China are off to a bumpy start. Mr. Trump is set to meet with China’s president, Xi Jinping, next month at his Mar-a-Lago estate in Florida, where issues like trade policy and disputed territorial rights in the South China Sea will most likely be on the table.

Richard W. Painter, who served as an ethics lawyer in the administration of President George W. Bush, said the sale of the Chinese bank shares made sense, given China’s importance on the global economic stage.

“If we get into a big spat with China, it is obviously going to have an effect on that bank economically,” Mr. Painter said. “There is no way you should be a senior adviser on economic or military policy, and have a big stake in a Chinese bank. That’s an invitation for trouble.”

The ethics documents issued to Mr. Cohn, known as certificates of divestiture, and a separate set issued to his wife, Lisa Pevaroff-Cohn, indicate that the couple will reinvest the proceeds of the Chinese bank stock sale and other asset sales into certain widely held assets, like Treasury bills or exchange-traded funds.

The certificates of divestiture issued on March 8 are not a complete picture of Mr. Cohn’s assets. They list only those that he and Ms. Pevaroff-Cohn will sell and then reinvest as a means of legally avoiding certain capital-gains taxes. Once the positions listed in the documents are liquidated, the couple will have 60 days to make the new investments.

But the documents do provide a window into the assets that Mr. Cohn and his wife held at the end of his 26-year tenure at Goldman Sachs, from which he resigned in December.

In addition to his stake in the Chinese bank, Mr. Cohn is selling roughly $216 million in Goldman stock, plus 18 other stocks, and plans to reinvest the proceeds.

The other holdings include some major consumer brands, like the tobacco companies Philip Morris and Reynolds American, as well as the food company Kraft Heinz; and a passel of tech companies including Facebook, Twitter, Box, Intel, HP and Hewlett Packard Enterprise. Aside from Goldman, his holdings include only one other major United States bank, Bank of America. (Mr. Cohn is selling 9,174 Bank of America shares, valued at roughly $230,000.)

Taken together, Mr. Cohn and Ms. Pevaroff-Cohn are selling small minority stakes in 11 private investment vehicles, including a group of Goldman Sachs-operated private equity funds, some of which were set up specifically for firm employees.

Mr. Cohn’s detailed ethics plan and personal financial disclosure statement, which would include further information about his income and assets, have not yet been made public.

In a filing on Jan. 24, Goldman Sachs explained that because of Mr. Cohn’s new government role, he would sell stakes in a variety of private equity funds and hedge funds managed by the firm. In some cases, the stakes were repurchased by Goldman itself, at a discount.

Mr. Cohn is not the only Goldman Sachs executive to invest in the Industrial and Commercial Bank of China. When he became Treasury secretary in 2006, the former Goldman chief executive Henry M. Paulson Jr. sold an individual position worth as much as $25 million in the bank, according to government documents issued at the time.

Goldman itself held a sizable position in the Chinese bank for seven years, selling the last block of it to end the investment in 2013.