* Says no change to merger terms
* Merger benefits both Singapore and Australia
* Swan says to carefully consider SGX response in coming to his final decision
* SGX shares fall as much as 3.1 percent on uncertainty (Adds Treasurer statement, updates share price)
By Saeed Azhar
SINGAPORE, April 7 (Reuters) - Singapore Exchange said on Thursday it has provided Australia's Foreign Investment Review Board (FIRB) with further written responses regarding its $7.8 billion takeover bid for ASX , a sign it has not given up hope on the deal.
The statement follows Tuesday's comments from Australian Treasurer Wayne Swan that he intends to reject SGX's bid for Australian bourse operator ASX on national interest grounds.[ID:nL3E7F50PP]
"SGX has today provided further written responses to the FIRB in connection to the ASX-SGX merger proposal. SGX has not amended the terms of the proposed merger," SGX said in a short statement.
It did not disclose the details of what it has written in its response.
A source familiar with the deal said SGX wants Australia to formally reject the bid for ASX, which would force the government to put its reasons in writing.
"This would make it harder for someone else to go after ASX as the objections would also apply," the source said.
Australia's Swan said in a statement that he will consider the SGX response.
"I will carefully consider this response in coming to my final decision and will make a public statement as soon as possible."
The statement from SGX said SGX and ASX maintain their belief that the merger proposal would result in significant benefits for Australia and Singapore.
Australian Treasurer Swan is expected to publish his reasons for officially objecting to the bid as early as this Sunday, the Australian Financial Review said in a report on Thursday without citing its sources.
Another source familiar with the transaction said SGX also expected to hear from the government as early as this weekend.
The Australian government had concerns that an SGX takeover could impact the ability of Australian regulators to protect the country's financial settlement systems from future global financial crises or cause disruption to the delivery of clearance services, the report in the Australian Financial Review said.
"Read Swan's comments to the press in Australia and tell me what you think," said Derek Ovington, banking analyst at CLSA in Singapore.
"He doesn't sound to me like he's open to changing his mind. You never say never in these situations, as he did state originally that his decision was not final, but it sounds pretty final to me. Hopefully it won't take too long before we all find out."
ASX shares ended 0.8 percent lower at A$33.48 in Sydney trade Thursday. SGX shares were down 2.3 percent, underperforming a 0.32 percent fall in the broader Singapore market .
SGX had rallied as much as 6 percent after Tuesday's news that the deal will be rejected and extended gains on Wednesday.
"Yesterday the share price shot up because people assumed that the deal was totally dead. But I think it was an over-reaction," said a Singapore dealer.
"It's not confirmed that Australia will reject the deal. There is some remote chance that it will still go through." (Additional reporting by Kevin Lim and Eveline Danubrata in SINGAPORE and Michael Smith in SYDNEY; Editing by Matt Driskill)