Sweden’s leaders came forward to express deep concern after a report alleged that the country’s spy agency has close ties with the NSA and GCHQ, and is the third major partner in surveillance cooperation.

"It's a very serious matter if Sweden is indeed involved in American surveillance programs," Green Party IT policy spokeswoman Maria Ferm told Sweden’s The Local. "I'm very concerned about the information that came up in the hearing," she said.

According to a report in the Metro daily, investigative journalist Duncan Campbell disclosed information about Sweden’s ties to the NSA during a hearing on the wiretapping scandal of a committee in the European Parliament.

Campbell revealed that the Swedish National Defence Radio Establishment (FRA) provided the NSA and Britain’s Government Communications Headquarters (GCHQ) access to Baltic underwater cables. He added that Sweden was the third major partner in surveillance cooperation.

The FRA declined to comment on the report.

The European Parliament's Committee on Civil Liberties, which was created to research the wiretapping scandal, launched a series of hearings on Thursday.

The goal of the committee is to find out how EU citizens have been affected by US and UK surveillance.

"It's deeply troubling if Sweden is participating in surveillance operations that are as extensive as those of the United States and that attempt to circumvent national laws," stated Ferm.

Sweden's Democracy Minister, Birgitta Ohlsson of the Liberal Party (Folkpartiet), also expressed her concern.

"I absolutely think this is not good. I've also been engaged in issues related to personal privacy and transparency in Sweden and I think in all countries, including Sweden, the EU, and the United States...that things have gone too far," she said during an interview with Sveriges Television (SVT).

Other politicians were not surprised by the revelations.

"It's hard for me to be surprised by information about FRA/NSA cooperation. Been convinced the whole time that the point of FRA is to provide the USA more info," Fredrik Federley of the Centre Party wrote on his Twitter account. Federley is a critic of the controversial “FRA-law” in Sweden, which gives the government the power to eavesdrop on telephone calls and internet traffic.

In response to the allegations, Defense Minister Karin Enström of the Moderate Party said in a statement that Sweden’s intelligence cooperation with other countries is "critical for our security," with rules that "balance security and privacy interests.”

"Intelligence operations occur within a framework with clear legislation, with strict controls, and under parliamentary oversight," the statement read.

Politicians have stepped forward in Sweden, demanding that the government come clean.

Foreign policy spokesman for the Left Party, Hans Linde, called for the government to "put all its cards on the table" with respect to how Swedish and US intelligence agencies cooperate.

Ferm also asked the government to explain what really happened. "The government needs to tell us what's going on," she said, adding that she has called on Foreign Minister Carl Bildt and Justice Minister Beatrice Ask to answer questions in parliament.

News of the report emerged just one day after additional top-secret documents from whistleblower Edward Snowden were leaked to the media. The information revealed that the NSA and GCHQ have circumvented encryption methods used to secure emails, chats, and essentially most internet traffic that was previously thought to be protected.