Aston Villa travel to Manchester on Sunday looking to respond to their 3-0 Champions League defeat by Barcelona, with Emery expecting a difficult test against Michael Carrick’s side.
The Spaniard has never won in 11 previous visits to Old Trafford, but he was keen to underline the stature of the club and the quality he believes United possess, despite their inconsistent domestic form.
“We lost to Barcelona because of the level we faced — the highest level in the Champions League. Manchester United is at the same level as Barcelona,” Emery said.
“Man United are a fantastic club. They were performing very well and achieved the Champions League.
“And this season they are playing well in the Champions League. They have not been consistent in the league but they should recover, hopefully not against us. It’s a difficult match.”
Emery also recalled previous unsuccessful visits to Old Trafford, including a Carabao Cup defeat, as Villa prepare for another attempt to end their poor record at the ground.
The manager's comments come amid speculation linking him with the United job, with Carrick under pressure despite the team's dramatic 3-2 Champions League victory over Roma.
However, Emery appears increasingly likely to commit his future to Villa. Discussions over an extension to his current contract, which runs until 2029, are expected to continue after a positive meeting with chairman and co-owner Nassef Sawiris.
“I had a good meeting with the chairman Nassef Sawiris — very positive,” Emery said.
“Let’s talk next week, to try to get everything we spoke about together in a deal.”
The 55-year-old has made clear that he wants Villa to build towards competing for the biggest honours in European football. He believes the club's history and recent progress provide a platform for further ambition, pointing to the 1982 European Cup triumph as evidence that Villa have previously reached the summit.
“Were they favourites then? I think not,” he said, before citing Leicester's Premier League title success and the European runs of Villarreal and Borussia Dortmund as examples of what can be achieved.
“In football, everything can happen. At Villarreal we played in the semi-final four years ago. Borussia Dortmund played three years ago in the final. Teams who are not favourites sometimes have the opportunity to fight for a title. I have my dreams.”
Emery also reflected on Villa's Europa League success last season, insisting that he remains focused on taking the club forward.
“I set my demands high, sometimes achieving them and sometimes not. Last year we won the Europa League, and I’m still being positive how we can continue improving.”
He believes his ambitions are shared by the club's ownership, with the relationship between manager and chairman central to the long-term project.
“We’re on the same page. His commitment to the club is a huge comment on everything,” Emery added.
For now, his attention is on the challenge at Old Trafford. But with contract discussions progressing, Villa will hope the next stage of Emery's project is built around keeping the manager who has helped restore their standing in Europe.