Democratic U.S. Senators Charles E. Schumer and Kirsten Gillibrand and Republican Rep. Elise Stefanik are among New York lawmakers who have sent a letter urging President Barack Obama to address what they see as unfair trade practices by Canada that harm New York dairy farmers and processors.

In a statement released with the text of the letter, the lawmakers said they want the president to address “Canada’s restrictive and arbitrary trade barriers” and to “preserve market access as negotiated under the NAFTA agreement.”

“We must take all necessary actions to eliminate unfair barriers to trade and preserve access for our dairy farmers,” the letter says.

“New York dairy companies have made substantial investments to produce a product intended specifically for export to Canadian cheese manufacturers. This investment and the sales that followed were made in response to the duty-free access secured under the North American Free Trade Agreement,” lawmakers wrote in their joint letter.

“Dairy companies from our state indicated they have already lost considerable export sales as a result of pricing policies. The proposed regulations limit the opportunity of U.S. dairy exporters. It is imperative that the Administration take decisive action and reject Canada’s restrictive trade policies and reinforce the value of concessions previously secured under NAFTA,” they said in the letter.