Australian shadow treasurer Joe Hockey questioned the merger of the Australian Stock Exchange (ASX) and the Singapore Exchange expressing doubt the merger is in the best interest of Australia.

Hockey said: "I want to hear from (Treasurer) Wayne Swan why the ASX being taken over by the Singapore Stock Exchange is in our national interest."

Hockey told Seven Network that he wants to know from the ASX and the government if the move would boost Australia's bid to be the next Asia-Pacific region financial centre. He asked the question as Singapore is Australia's biggest competitor for jobs in the financial service.

Hockey said that ASX is "iconic" for Australia since it is effectively a monopoly. However, he also welcomed foreign investments and remains uncritical of foreign ownership in Australia.

Nevertheless, Hockey still have reservations that an Australian market monopoly was bought out by an "overseas interest."