TORONTO - TMX Group Inc. (TSX:X) will hold formal discussions with Maple Group Acquisition Corp., which has made a $3.7-billion takeover bid for the operator of the Toronto Stock Exchange.

TMX said late Thursday its directors aren't making any recommendation to shareholders regarding Maple's offer, adding there is no guarantee that any agreement between the two sides will come out of the talks.

After the collapse of a previous merger deal between TMX and the owner of the London Stock Exchange, TMX Group chief executive Tom Kloet said he was open to all opportunities, including discussions with Maple.

The 13-member Maple Group includes some of Canada's largest banks, pension funds, investment funds and one insurance company. It is the only remaining suitor for the operator of Canada's largest stock exchange.

Maple Group said Thursday it has entered into a confidentiality agreement with TMX Group regarding the proposed acquisition talks.

"We look forward to engaging in collaborative discussions with TMX Group," Maple spokesman Luc Bertrand said in the statement.

"While there can be no assurance that these discussions will ultimately lead to a TMX Group Board supported transaction, the signing of this agreement and the commencement of discussions is a positive step."

Maple said the talks with TMX Group won't affect the status of its current offer of $50 per share, which its scheduled to expire on Aug. 8.

The TMX had originally brushed off the offer as saddling the company with too much debt.

If the acquisition proceeds, the deal would need to be approved by Canada's Competition Bureau.

As part of its bid, Maple plans to buy all of Alpha and CDS Inc., a clearing and depository firm, and add them to TMX Group to create a bigger Canadian-based exchange.

Some critics have said that would create a virtual monopoly that could lead to higher fees and create enforcement and transparency issues.

Maple has said it is confident its offer to acquire TMX, Alpha and CDS can obtain all required shareholder and regulatory approvals and that there would still be vigorous competition in equities trading.