An online U.S. cattle auction that ranchers and traders hope will restore transparency to livestock pricing and reduce volatility in futures contracts is set to resume operations in September following a three-month halt, its owner said on Thursday.

Separately, a U.S. watchdog agency said it will take at least nine months to complete a government review of U.S. cattle markets that was prompted by complaints about a sharp drop in prices last year.

The online auction, called the Fed Cattle Exchange, and the review by the U.S. Government Accountability Office (GAO) aim to address concerns that cash and futures prices do not accurately reflect the markets for cattle. The markets have come under scrutiny following a sharp setback in prices in the second half of last year from record levels reached in 2014.

The Fed Cattle Exchange wants to increase the number of cattle traded in the cash market before slaughter in a bid to provide the sector with a better idea of their value.

It will begin holding weekly auctions on Sept. 14 after fixing technological problems that hampered its first several sessions in May and June, said Danny Jones, president of exchange owner Superior Livestock Auction.

"We are going to go forward with the attitude that this is definitely working now and it's got the weight of the industry supporting it," he said in an interview.

Cash sales of cattle, which producers and meat packers negotiate a few weeks before animals are killed, have dropped over the past decade as producers have increasingly locked in prices months in advance. Futures exchange operator CME Group Inc has said that decline has contributed to high volatility in its cattle market.

Once the auctions resume, the exchange will post results on its website shortly after they conclude, Jones said.

The biggest U.S. meat packers, Cargill Inc, Tyson Foods Inc, JBS USA and National Beef Packing Co , bought cattle on the exchange before Superior suspended auctions in June, participants said.

Separately, the U.S. government's review of cattle pricing is underway and will last at least until May 2017, GAO spokesman Chuck Young said in an interview.

The agency has previously said the review will include an assessment of the impact of high-frequency trading on cattle futures and "what changes may have occurred in the fed cattle market in the past 10 years."