The United States and Canada were working through final trade issues Friday as a deadline approached that could bring steep new tariffs on Canadian goods.

CNN reported that the United States could impose 50% tariffs on about $20 billion worth of Canadian imports if the two governments fail to complete an agreement before the deadline. Negotiators have been discussing several long-running trade disputes involving steel, aluminum, automobiles and agricultural products.

Canadian concessions under discussion also include changes affecting American products sold north of the border. Provincial restrictions on US alcohol, introduced during earlier trade tensions, have become part of the negotiations, with Canada considering steps that would allow American liquor back onto store shelves.

The talks carry particular importance for industries that depend on cross-border supply chains. Auto manufacturing is one example, with production networks closely linked between the two countries.

Both governments have indicated that progress has been made, but unresolved issues remain as negotiations continue toward the deadline.