The US has rejected an offee to merge the Chicago Stock Exchange and a Chinese-linked investor group.
The proposed acquisition had been approved in late 2016 by the Committee on Foreign Investment in the United States, which reviews deals for national security concerns.
Lawmakers in the U.S from both sides harshly criticized the deal through joint letters sent to the SEC, saying that it would allow the government of China to have access to the financial markets of the US and questioned the ability of the SEC to monitor and regulate foreign owners.
A group led by China's Chongqing Casin Enterprise Group had proposed acquiring CHX for $20 million.
Supporters of the deal said it could attract more Chinese companies to US financial markets and help revive a marketplace where activity was dwindling, but critics raised concerns about Chinese interference in the USA economy.
The Chicago Stock Exchange, in a blog post Friday, said it was disappointed with the decision. The regulator said this "raises significant doubts" that it would be able to monitor the exchange if the deal went through.
"By disapproving the transaction, the SEC has denied the American public an historic and unprecedented opportunity to build a mutually beneficial economic bridge between the world's largest economies, while unfairly disadvantaging our company and shareholders", the exchange said. The exchange said it needed the infusion of capital to invest in its operations and attract business.
"I fear that that the challenges plaguing the Chinese market-lack of transparency, currency manipulation, etc. -will bleed into the Chicago Stock Exchange and adversely impact financial markets across the country", Manchin said in his statement provided to Breitbart News exclusively.
SEC staff approved that plan in October, but the SEC commissioners also put that decision on hold and there is no deadline for a further ruling.
CHX competes against the New York Stock Exchange and its three affiliated exchanges, all owned by Intercontinental Exchange Inc, and Nasdaq Inc and Cboe Global Markets Inc, both of which own four United States stock exchanges.