13/01/2016 1:31 PM AEDT | Updated 15/07/2016 12:51 PM AEST

Australians Are Buying Tickets In The $2.1 Billion US Powerball

SAUL LOEB via Getty Images
A man walks past a sign showing a Powerball prize of $999 million, the largest jackpot winnings that the Powerball sign can display, with the actual Powerball jackpot estimated at $1.3 billion, outside a deli in Washington, DC, January 11, 2016. The jackpot for the US Powerball lottery rose to a whopping $1.3 billion (1.19 billion euros) on January 10, by far the largest in US history, after organizers said there was no winner in the weekend draw. The Powerball prize rocketed to $950 million on Saturday, fueling a frenzy of lotto ticket buying across the United States. Numbers were drawn and announced late Saturday at 10:59 pm (0359 GMT Sunday) -- but hours later lottery officials said there was no winner. AFP PHOTO / SAUL LOEB / AFP / SAUL LOEB (Photo credit should read SAUL LOEB/AFP/Getty Images)

Australians are clamoring to get their hands on tickets for the U.S. Powerball jackpot as it climbs to $2.1 billion but authorities are warning buyers to be wary.

The lottery, to be drawn Thursday morning AEST, is officially the world's largest prize at $US1.5 billion. Like the Australian Powerball, ticket holders choose five numbers between 1 and 69 as well as an all-important 'powerball' number between 1 and 26.

Every time a winner is not found, the jackpot goes up.

According to University of Buffalo statistician Jeffrey Miecznikowski's comments to Wired this week, the chances of winning this Powerball about one in 292 million.

Plenty of Australians seemingly like those odds because third-party lottery ticket buying companies like The Lotter said more than 1000 Australians had purchased tickets.

The company sends 'lottery experts' to purchase tickets in lotteries around the world on behalf of customers. The buyer scans the ticket and send it to the buyer. The company says it has distributed more than $60 million in prize money since it launched in 2002.

Another company Lottoland is also offering U.S. Powerball tickets to Australians, having been awarded a five-year license by the Northern Territory Racing Commission to open online gambling in international lotteries.

A spokesman for the NSW Office of Liquor, Gaming and Racing however, warned buyers would not be protected by the same controls and protections they'd expect when buying a lottery ticket in Australia.

"In relation to residents who have purchased tickets in an overseas lottery through a third party provider such as The Lotter, there are no controls or protections in legislation administered by the Office of Liquor, Gaming and Racing in relation to the service provided by the third party," the spokesman said.

"[In Australian states and territories], the rules for each lottery stipulate that prizes for each game must be paid by the licensee, set out the range of prizes that must be paid by the licensee and outline the procedures for claiming prizes. The rules and associated terms and conditions, are contractually binding on both the licensee and the player."