Although they were originally slated to hit UK shelves alongside Sony's next gen machine in March, Koei's Fatal Inertia and Bladestorm: The Hundred Years War have now slipped to the summer.

While it's undoubtedly a shame the two titles are being delayed, gamers can be assured the Dynasty Warriors publisher will be slaving away on the games right up until release "to ensure the highest levels of quality possible".

Set in the 23rd Century, Fatal Inertia mixes street racing, demolition derbies and rallying in a futuristic setting where cars don't need wheels (WipEout anyone?) and the laws of physics govern all. Meanwhile, Bladestorm will turn the drama of war-torn medieval Europe into a tactical action game featuring heroes like Joan of Arc.

Both titles are also due to be released on Xbox 360, but Koei has yet to announce whether these versions have also been delayed until the summer.