The Reds' record signing says Benitez must be backed in the transfer window if Liverpool are to challenge for the Premiership next season.
"If we can't keep up with them [Man United and Chelsea] economically, then we have to get it absolutely right in the transfer market," said Torres.
"It's clear that they have a lot of £20m or £25m players, and that difference is what separates us in the table.
"I hope that the club does what needs to be done and we can quickly catch them up."