State-owned investment management firm Temasek Holdings Ltd of Singapore downplayed the influence of politics on the controversial merger deal between the Singapore Stock Exchange (SGX) and Australian Securities Exchange (ASX).

In statement posted on its official website, Temasek said that despite its 23.45 percent ownership in the Singaporean stock market management, its day-to-day operations and executive decisions were far from its control.

The open letter was also addressed to the Australian media and was made public following the political debate that erupted in Australia in light of the $US8.2 billion or $A8.31 billion takeover offer by the Singapore Exchange for the ASX.

Temasek executive director Simon Israel clarified in the open letter that the firm's "board and management make our investment, divestment and other company decisions on a commercial basis, independently of our shareholder, the Singapore government."

Mr Israel further stressed that notwithstanding its hefty interest on the city-state's stock market, Temasek is not a party in governing, operating and decision making of the SGX as he pointed to an annual report of the stock operator which confirms its 23.45 percent holdings in he bourse do not constitute any voting rights.

The stock market merger between Australia and Singapore is in danger of meeting derailment as a number of independent MPs called for the dumping of the deal, citing that ceding the country's stock exchange directly runs counter with national interest.

Also, the Coalition scored the deal as it raised fears that the healthy state of competition in the country's financial sector could be compromised by the foreign takeover of the ASX.