Poker players in the U.S. who win big in the nation’s casinos and card rooms will no longer be able to keep their winnings a secret from Uncle Sam.

Starting this week, all American casinos and card rooms will be required by law to report to the Internal Revenue Service (IRS) anyone who wins $5,000 or more playing in a poker tournament.

The law was originally to require casinos and card rooms to withold 25% of all poker tournament winnings for tax purposes, but was loosened after outcries from the poker community.

“It allows the IRS to keep track of poker players, because poker is real big now,” Marissa Chien, co-author of the book ‘Tax Help For Gamblers,’ told the Associated Press.

“If you’re already reporting your income and being truthful and honest, this shouldn’t affect you one bit,” Chien said.

“But for those who try to stay off the radar, this is going to make it that much harder.”

Kevin Lillo, a poker room shift manager at the Trump Taj Mahal hotel and casino in Atlantic City, told the A.P. the new tax law will be an “inconvenience.”=9D

He continued: “It’s always been the law to report winnings. All they’re doing is making the casino enforce it. They’re seeing money that’s falling through the cracks.”

The new law will not affect those who win monies playing in poker cash games at casinos and card rooms, because that is too hard for the casino to track.

By law, however, those winners, plus those who win at other casino games such as blackjack, roulette and craps, are required to voluntarily report their gambling winnings on their annual tax returns.

(E-mail Tom Somach at tomsomach@yahoo.com.)