The largest and most important mobile network in Denmark, TDC's 4G-network, will be operated by the Chinese IT company Huawei by the start of 2015.
The government approved the deal between Denmark's largest phone company and Huawei despite warnings from the US and the UK that the Chinese government could carry out espionage through Huawei's equipment.
The head of the military's Institute of Strategy, Peter Kim Lausten, is concerned that Denmark has made itself vulnerable to espionage by allowing the Chinese company access to the Danish 4G mobile broadband network.
"When there is a strong state with powerful companies that have unclear owners, it is likely that the state in some situations will use the company for other things than just making money," Lausten told Politiken newspaper.
Banned in US
The US Congress denied Huawei access to the American market because the House Committee on Homeland Security assessed the company would pose a threat to national security.
In June, former CIA and NSA head Michael Hayden told the Financial Review that he had seen evidence that Huawei conducted espionage for the Chinese state.
"At a minimum, Huawei would have shared with the Chinese state intimate and extensive knowledge of the foreign telecommunications systems it is involved with," he said.
The deal with TDC and Huawei means that equipment and software has to be disassembled and analysed by a special security centre known as 'The Cell', which is made up of Huawei's own safety staff.
The UK signed a multi-billion pound deal with Huawei in 2005 to supply the British Telecommunications Group, but the British Parliament's Intelligence and Security Committee accused the The Cell of "self-policing" in a report earlier this year.
The committee demanded that all employees of The Cell be government-appointed employees of British Intelligence agencies, and PM David Cameron's national security adviser is currently reviewing the committee's report.
The Defence Ministry's internet security centre, Center for Cybersikkerhed (CFB) worked closely with TDC prior to the deal and has approved of the way The Cell operates.
The head of CFB, Thomas Lund Sørensen, said he found it "adequately assuring."
"We will of course follow the discussion taking place in Britain at the moment and we are waiting for the final report from the PM's security adviser," Sørensen told Politiken.