Bertrand Delanoe, who was in Quebec to attend an international forum on the French language, wanted to be briefed on the students' opposition to tuition fee increases that would still have them paying some of the lowest fees in Canada.
Charest said after a ceremony at the legislature where Delanoe was invested as an officer of the Order of Quebec that the socialist politician was free to meet with representatives of "civil society."
"There was never any question of him condoning anything and on this he was very clear,'' Charest told a news conference. "To suggest the opposite would be the opposite of the truth.''
Charest said Delanoe had proved his neutrality on the tuition fee issue by refusing to allow a debate on it by Parisian municipal politicians.
There have been several sympathy demonstrations for the Quebec students in the French capital during the last few weeks.
Delanoe said after the investiture ceremony that he was interested in the students' side of the debate.
''Quebec is a democracy and we do not interfere in the democratic debates of its population," he said. "While I was here, I wanted to listen — and I mean listen — to the student associations to try and understand why they took their positions. But of course I am not taking sides."
Delanoe, who met with leaders of three student groups, didn't refer to the tuition fee dispute in his acceptance speech but acknowledged he and Charest don't always agree despite their friendship.
"It's true we have developed a personal friendship and maybe had a few political differences.''
Earlier, Martine Desjardins, president of the Quebec university students' federation, said Delanoe remained objective but was interested in how the tuition fee increase would affect French students in Quebec. She said the meeting was set up about two weeks ago.
However, she added the very fact the Paris mayor had sought a meeting with the students lends credibility to their cause.
"It's been clear from the start that we have credibility but the fact that the mayor wanted to meet with us shows that not only Quebecers are interested in this (issue)," Desjardins said.