Marathe made the comments during yesterday's bus parade after clinching the Championship title and promotion on the weekend.
"I don't think anyone realised, this wasn't f***ing easy. This was really hard to do. Two years of getting to this point, but all that hard work and all that difficulty makes this much more rewarding and makes this so special," said Marathe on the bus.
"This is a journey and this is not the end. We have to keep going.
"This is what Leeds does. We are going to have some difficulties, but we are going to get where we want to go and we are going to be one of the best clubs in all of Europe."
Yesterday's parade took three hours through the city centre, as Leeds fans celebrated their return to the Premier League after two seasons in the Championship.