Many retailers are using the threat of a potential tariff war to urge their customers to "buy now" before President-elect Donald Trump's proposed tariffs go into effect.

While Black Friday sales have become an American staple the past half century, the newly floated "pre-Trump tariff sales" might have an even greater impact on retailers' bottom line. Both large and small business have told their customers to take advantage of current prices, because they won't last if a global tariff war takes hold.

On Monday, Trump threatened to impose sweeping new tariffs on Mexico, Canada, and China as soon as he takes office as part of his effort to crack down on illegal immigration and drugs. He said he would impose a 25% tax on all products entering the country from Canada and Mexico and an additional 10% tariff on goods from China as one of his first executive orders.

The National Retail Federation has estimated that an import tariff between 10% and 20% will simply be passed on to the consumer, costing Americans billions of dollars each year.

"If the tariffs go into effect at the levels that have been spoken about, retailers will have no choice but to put up prices," GlobalData Managing Director Neil Saunders, told CBS News. "So one of the things they will have to do is pass some of those cost increases over to consumers in the form of higher prices."

Maryland-based fishing rod seller J&J Sports Service warned customers to "buy now" because impending tariffs "are not a joke."

"Our rods are built here but the supplies come from other places Japan in general. We will hold the line as long as we can, But we can say for certain this may be the last 'sale' you may see," the retailer wrote on Facebook.

Last week, online retailer Finally Home Furnishings told their customers that their prices will "double" once Trump's plan take effect. "Pre-Tariff Sale! This is not a drill. The very same items you are seeing now will be double the price once the tariffs kick in. This is not speculation. We went through this 4 years ago."

Yet some retail experts speculate that even those retailers whose products may not be affected by potential tariffs could use the threat as an excuse to raise prices.

"If consumers panic about things getting more expensive, they are playing right into the hands of companies around the country to use it as an excuse to raise prices, even when it's not necessary," said Cato Institute's Scott Lincicome. "It's a pretty handy excuse when you are in a constant battle with consumers on price."

Information from The Associated Press was used in this report.

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