Lukaku is expected to complete a club record £98m move from Inter Milan to Stamford Bridge in the coming days.
Werner joined Chelsea from RB Leipzig for £47m last summer but could not replicate his impressive scoring form from Germany in England as he passed up a number of clear cut opportunities.
The Germany international only scored 12 goals in all competitions for the Blues but laid on 15 assists for his teammates and ended the campaign as a European champion as Chelsea defeated Manchester City in the UEFA Champions League final.
Werner is adamant that his numbers will improve in the upcoming season if he gets the chance to feature alongside the Belgium international under Thomas Tuchel.
"He's probably one of the best three strikers in the world at the moment," Werner told Sky Sports when quizzed on Lukaku. "There is no question about that. I don't think we need to say too much about him. He's a world-class striker who would benefit any team.
"I certainly think at Leipzig that it always helped me having a big striker alongside me. I think that's always good because I'm not the biggest and when you play up front on your own, you always have the attention of one or two defenders.
"It's a good new weapon to have in our game when you know that if you play a long ball, he will hold it up. And then the fast players around him can the set off - I think that's good for any team."
Werner is expected to feature when Chelsea face Villarreal in the UEFA Super Cup final in Belfast later on Wednesday.
