According to a insider, it sounds like a rumours that Yaris will go for Hybrid like the Honda FIT Hybrid. By going Hybrid for Toyota Yaris would be unnecessary, according to the unnamed source.

Today's Toyota Yaris is already a fuel miser. The European variant is currently equipped with a 1.3-litre dual VVT-i engine with start-stop technology allowing the compact runabout to earn an impressive 55.4 mpg combined fuel economy. While dropping a hybrid powerplant into a larger vehicle pays back significantly, the gains realized by building a hybrid Yaris would be negligible.