Two U.S. congressional committees this week demanded Swiss engineering firm ABB provide testimony and additional details about its operations in China.

The Republican-led House Homeland Security Committee and Select Committee on China, as well as two subcommittees, sent a letter on January 16 to the group’s executives inviting them to public hearings to clarify the company's relationship with a Chinese state-owned company that they said raised “significant concerns.”

The missive, a followup to one sent last year, specifically cited concerns over the installation of ABB equipment by Shanghai Zhenhua Heavy Industries, a state-owned Chinese company, on ship-to-shore cranes delivered to the U.S.

The Swiss company provided documents to the original congressional requests, and cooperated with lawmakers in other ways, such as allowing lawmakers to meet with personnel and counsel, but those negotiations have since broken down, according to the latest letter.

Lawmakers want information and documents about possible "cybersecurity risks, foreign intelligence threats, and supply chain vulnerabilities at seaports” in the U.S., according to the letter, which was first published by Politico.

"It is vital ... that ABB explains its relationships with PRC (People's Republic of China) state-owned enterprises, and whether ABB should be trusted to continue working on behalf of U.S. government agencies while simultaneously engaging with entities owned, controlled, subsidized, or influenced by the PRC," the group said.

"Allowing ZPMC to install ABB equipment and technology in China onto cranes bound for the United States is unacceptable and must be remedied without any further delay."

In a statement, ABB said it supplies “standardized electrical and automation software and hardware for cranes used in ports around the world, including the U.S. ABB's crane software technology is supplier-independent and installed on cranes manufactured by major crane builders including Chinese companies.

“These cranes are bought by U.S. ports from Chinese and other companies, not from ABB.”

The company said it would take the request for further information "seriously."