England followed up their opening win over Grand Slam winners Ireland, by thrashing France 44-8 at Twickenham on Sunday to set up a potential Six Nations title decider against Wales in Cardiff.
Wales won their 11th successive Test by beating Italy on Saturday, equalling a century-old national record, and Jones is well aware of the task that faces his side on February 23.
"We are playing the greatest Welsh side ever.
"That's what we are hearing, we'll take it at face value," said Jones speaking after the win over France.
"We're going to have to be at our absolute best. Preparation starts on Wednesday.
"You're playing against a tough, physical team. They contest hard at the breakdown. You've got to earn every point against them.
"We're looking forward to going down there. It should be fun."