US chat show host Ellen DeGeneres has been slammed as ignorant and disrespectful after making a controversial joke during the USA v Ghana World Cup match.

The 56-year-old star was amongst the millions of fans across the world who tuned in to watch what was billed as the ultimate rematch, four years on from an infamous clash between the two nations at the last World Cup.

After America's Clint Dempsey scored the opening goal just 32 seconds into the game, Degeneres took to Twitter to express her pride.

"Go USA! Fastest goal in U.S World Cup History in the #USAvsGhana game. 32 seconds! It took me longer to look up where Ghana is."

Although it is not clear whether the presenter really doesn't know where the West African nation is, many struggled to see the funny side.

Members of the African community soon took to social media to vent their outrage, with some insisting that she should know better as a well-respected celebrity.

"Now if someone made a homophobic or anti-animal joke Ellen would be up in arms. But it's ok for her to make an ignorant joke like this," one critic wrote.

To add salt to the wound, although Ghana equalised with seven minutes left, a goal from the USA's John Brooks gave them the victory they desperately craved.

Degeneres has since deleted the gaff but is yet to issue an apology.