Mahrez, 27, completed a £60m switch on Tuesday and upon his unveling he said he arrives to 'improve' an already 'big club.'
City won the Premier League title on record-breaking fashion last season under Pep Guardiola, but Mahrez is confident his talents will be able to help the Sky Blues improve domestically and in Europe.
"City have ambition to go further than the Champions League quarter-finals like they did last season," he told the club's website.
"I made the decision to come here because I want to be part of that.
"The Champions League is for big clubs. They're a big club, they have everything to try to win it."