CIA Director Mike Pompeo failed to disclose last year that he owned a Kansas business that imported oilfield equipment from a company owned by the Chinese government.

That omission, on the questionnaire Pompeo was required to fill out for Senate confirmation to lead the spy agency, could cause a problem for him in Thursday’s confirmation hearing before the Senate Foreign Relations Committee to be President Donald Trump’s secretary of state.

The issue with the Chinese company, which was confirmed in a series of documents obtained by McClatchy this week, never came up during his confirmation hearings last year. Many senators contacted Wednesday were reluctant to comment until they had more information.

Sen. Ben Cardin, D-Md., a committee member, said he was unfamiliar with the discrepancy, but said it was troubling. “If there’s an inconsistency in his questionnaire, that would be a matter of major interest,” Cardin said.

After the story published, Sen. Bob Menendez, D-N.J., said his staff had already contacted the State Department about the omission and he plans to ask Pompeo “formally, directly” in his “QFR” — question for the record.

“It’s concerning, depending on what the facts are,” he said. “Not having something is concerning to me.”

With Sen. Rand Paul, R-Ky., opposed and Sen. John McCain, R-Ariz., out battling cancer, Pompeo needs some Democrats to be confirmed.

Already, Democrats who voted for Pompeo last year but are vulnerable in this year’s congressional elections are wary about committing to the former Kansas congressman this time. He was confirmed as CIA director last year by a vote of 66 to 32, with 14 Democrats voting for him.

“Mr. Pompeo was president of an American company in Kansas that sold products made in many different countries, Canada and China to name just two. In fact, the paper clips the company used were from Taiwan,” a CIA spokesman said. “He would have no reason to know details on the layers of companies that may or may not have had ownership interests in each overseas company that supplied products to his Kansas company.”

Pompeo’s new questionnaire submitted to the Senate Foreign Relations Committee for his new job nomination is not publicly available.

Last year the questionnaire he filled out for the Senate intelligence committee asked: “During the past 10 years, have you or your spouse received any compensation from, or been involved in any financial or business transactions with, a foreign government or any entity controlled by a foreign government? If so, please provide details.”

He answered “no.”

“Director Pompeo either was somehow unaware he was doing business with a Chinese government-controlled company, or he knew, and decided to hide that fact from Congress,” Sen. Ron Wyden, D-Oregon, a member of the intelligence committee, said after the story published. “Neither option is acceptable for a man who would be responsible for our nation’s most sensitive diplomatic matters.”

But Sen. Richard Burr, R-N.C. chairman of the intelligence committee, shrugged off the incident, saying that Pompeo “didn’t disclose that he had purchased a pump that resold from a Chinese company. That’s like when you buy a pair of shoes at K-Mart.”

Pompeo, a three-term congressman from Wichita, served as president of Sentry International, which manufactures and sells oilfield equipment, from 2006 to 2010.

In November 2006, he registered SJ Petro Pump Investment LLC in Kansas. Pompeo and Sentry were both listed as owners of SJ Petro in its 2007 annual report filed with the Kansas Secretary of State’s office. In 2008, he was no longer listed as owning more than 5 percent of the company but was still a signing member.

Pompeo said at the time that SJ Petro Pump Investment acted as an agent that sells and distributes equipment made by a Chinese firm with a similar name, SJ Petro, according to an October 2010 story in the Wichita Eagle.

The Chinese business, SJ Petro or SJ Petroleum Machinery Co., is a subsidiary of Sinopec, one of the world’s largest oil and gas companies. It was majority owned by China Petrochemical Corporation, a state owned enterprise, according to its 2008 annual report.

In 2014, Sinopec and Sibur, a gas processing and petrochemical firm that is partially owned by the Russia government, announced the creation of a joint plant in Shanghai. In November, during Trump’s visit to China, Sinopec agreed to help develop a $43 billion natural gas project in Alaska.

Sinopec hired a lobbyist in Washington to represent the company in a variety of issues, including energy, trade, deregulation, in front of the administration and Congress in May 2016. The contract was continued.

Pompeo, a West Point and Harvard Law School graduate, was elected to Congress in 2010on a wave of tea party support and with backing from the Koch Industries political action committee.

Pompeo’s salary from Sentry International in 2010 was $238,364, according his 2010 financial disclosure report.

“Mike Pompeo lied about his business deals with a company owned by the Chinese government, so we can only imagine what else he isn’t being honest about,” said Harrell Kirstein, a spokesman for the Trump War Room director at American Bridge 21st Century, one of the liberal groups opposing his nomination. “What we do know is his former business partners (Sinopec) are spending more than $30,000 a month lobbying the Trump administration, and probably drooling over the idea of installing their pal as secretary of state.”

Cardin, who opposed Pompeo as CIA director because of his defense of torture to extract information from terror suspects, said he hasn’t decided how he’ll vote on Pompeo’s nomination to lead the State Department, saying he has “a lot of questions.”

He said Pompeo’s nomination presents challenges, including how strongly he will stand up to Trump if he disagrees with him, particularly on the Iran nuclear deal, North Korea and climate change.

Pompeo’s supporters and his critics stepped up their campaigns ahead of the committee hearing.

Liberal activists have pressured Senate Democrats to block Pompeo’s nomination, citing his support for expanding mass surveillance programs and defense of the CIA’s past use of torture.

A group of Republican-leaning national security experts that included former Attorney General Michael Mukasey, sent a letter to the Senate Foreign Relations Committee, saying Pompeo is “the sort of seasoned, accomplished and energetic national security policy practitioner our nation desperately needs at this juncture.”

And the Republican National Committee in an email urged senators to “support Pompeo, not partisanship.” It pointed to the January 2017 vote, listing the 14 Senate Democrats who had voted to confirm Pompeo as CIA director.

Sen. Bernie Sanders, I-Vt. was to headline a MoveOn.org protest outside the Capitol, urging senators to vote against Pompeo. “Like so many other Trump officials, including Trump himself, it turns out that Pompeo has failed to disclose extensive business dealings with foreign powers,” said Ben Wikler, Washington director for MoveOn.org.