Amazon.com fired a warning shot at North Carolina over a sales tax bill under consideration in that state. The online retail giant warned it will end its relationship with affiliates in North Carolina if the state legislature follows through on an "unconstitutional tax collection scheme."

Amazon currently collects sales tax in only a handful of states, but many state legislatures, facing severe budget shortfalls, are seeking to make Amazon collect sales tax on web purchases. The legislatures are looking to define Amazon as having a physical presence in their states (and thus a responsibility to collect sales tax) through locally based affiliates, who link shoppers to Amazon products in exchange for a cut of sales.

Here's the text of Amazon's email to North Carolina affiliates:

We regret to inform you that the North Carolina state legislature (the General Assembly) appears ready to enact an unconstitutional tax collection scheme that would leave Amazon.com little choice but to end its relationships with North Carolina-based Associates. You are receiving this e-mail because our records indicate that you are an Amazon Associate and resident of North Carolina.

Please note that this is not an immediate termination notice and you are still a valued participant in the Associates Program. All referral fees earned on qualified traffic will continue to be paid as planned.

But because the new law is drafted to go into effect once enacted – which could happen in the next two weeks – we will have to terminate the participation of all North Carolina residents in the Amazon Associates program on or before that same day. After the termination day, we will no longer pay any referral fees for customers referred to Amazon.com or Endless.com nor will we accept new applications for the Associates program from North Carolina residents.

The unfortunate consequences of this legislation on North Carolina residents like you were explained in detail to key senators and representatives in Raleigh, including the leadership of the Senate, House, and both chambers’ finance committees. Other states, including Maryland, Minnesota, and Tennessee, considered nearly identical schemes, but rejected these proposals largely because of the adverse impact on their states’ residents.

We thank you for being part of the Amazon Associates program, and we will apprise you of the General Assembly’s action on this matter.

North Carolina lawmakers are reportedly grappling with a $4.5 billion budget gap. Other states, following the lead of New York, have looked at making Amazon collect sales tax. Amazon has been fighting the New York law in court.

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