The Barossa’s Thorn-Clarke Wines has taken out two prestigious trophies at the London-based International Wine Challenge cementing South Australia's reputation as one of the world's leading wine regions.

The 2010 William Randell Shiraz was awarded the Trophy for the Best Barossa Shiraz and also Best Australian Shiraz against a field of outstanding wines.

According to IWC Co-chairman Charles Metcalfe, South Australia reaffirmed its status as the powerhouse of quality wine production in Australia, winning 10 of the 23 Trophies awarded to Australian wines at the 2013 IWC.

"Seven of the trophy-winning wines were made from different varietals, demonstrating the rich varietal and stylistic diversity within South Australia’s borders."

Thorn-Clarke Chief Executive Sam Clarke, speaking from the London Wine Trade Fair today, said that Australian winemakers can take heart from the high standards they set both domestically and internationally.

"Australian wines are consistently setting the pace for elegance and balance and they are worthy ambassadors of Australian culture,” he said.

“With an ever-strengthening reputation for quality, effective point-of-origin regulation and clean, green credentials, Australian wineries continue to be among the nation's most successful exporters.”

Mr Clarke said the 2010 William Randell Shiraz was awarded 97 points and a ranking in James Halliday's Top 100 wines for 2012 late last year.