The Jambos meet the Reds in the first leg at Tynecastle tomorrow prior to the return clash at Anfield a week later and former Liverpool star Souness, who grew up in Edinburgh, is of the belief that English football is way ahead of Scotland's teams giving Hearts little or no chance.
"There is a gulf between the Premier League in England and the SPL in Scotland right now," he said.
"Although Liverpool are not one of the great teams any more, they certainly still have good players.
"Andy Carroll can be unplayable if he gets the right service so you need to stop the ball getting to him. There are so many threats, maybe too many. It's not just Hearts. If Liverpool were playing any team in Scotland it would be the same.
"Hearts have always got an outside chance over the two games.
"They are the underdogs, though, and realistically you have to fancy Liverpool because of the quality of player they have.
"You're relying on lots of them having two off nights for Hearts to go through."