NASHVILLE (AP) — An association of brick-and-mortar retailers says a legal opinion from state Attorney General Bob Cooper should cancel a sales tax exemption for online merchant Amazon.com.

The opinion released Tuesday does not specifically refer to Amazon, but argues that "as a general rule" the state cannot waive requirements to collect sales taxes on items sold in Tennessee without specific legislation being passed by the Legislature.

But the opinion also notes that the state's revenue commissioner has "substantial discretion" — especially in cases where the tax law is debatable.

Former Democratic Gov. Phil Bredesen agreed last year to grant Amazon a waiver on collecting taxes as part of a deal that led to several distribution centers being built in the state. Traditional retailers have called that arrangement unfair, and Republican Gov. Bill Haslam's administration has been in talks to modify the deal.

"Any claim by Amazon that they merit a special deal in Tennessee is intellectually insulting and just plain wrong," Mike Cohen, spokesman for the Alliance for Main Street Fairness, said in a release. "Amazon must follow the law and collect sales taxes just like every other retailer in the state."

The opinion was requested by Sen. Randy McNally of Oak Ridge and Rep. Charles Sargent of Franklin. The Republican chairmen of the their respective chamber's finance committees earlier this year introduced legislation seeking to scuttle the tax arrangement with Amazon, but delayed consideration of the measure until next year.

Haslam told reporters after a speech to a Republican group at a Nashville law firm that he was not familiar with the details of the attorney general's opinion, but that he can envision supporting legislation next year to cement an eventual arrangement with Amazon.

"Hopefully we can come up with something that works for everybody sooner rather than later," Haslam said.

While tax agreements are confidential under Tennessee law, the governor said he is negotiating for the details to become public upon completion a new deal.

But Haslam said he would be concerned if every incentive deal with prospective investors had to be authorized by the General Assembly.

"Obviously that makes it a little more difficult if they have to green-light everything, because it is a competitive world," he said. "You know, we walk a balance between competing for jobs in a difficult economy and wanting to be as open about everything as we can."

Amazon has said it will employ more than 1,200 full-time workers at facilities in Hamilton, Bradley and Wilson counties, plus thousands more on a part-time or seasonal basis. The company has said it would be willing to collect the tax if a federal law covering all online retailers were enacted. But such regulations don't appear imminent.

Opponents of the sales tax deal in Tennessee point to last month's agreement by Amazon in California to begin collecting sales taxes in September 2012.