A new striker appears to figure prominently on Chelsea's transfer radar this summer, with question marks hanging over the respective futures of their current crop of forwards - Fernando Torres, Samuel Eto'o and Demba Ba.
Ibrahimovic, and in particular Cavani, have been linked with Premier League switches this coming summer, but Mourinho does not think that PSG will do business.
"Ibrahimovic? It's impossible," the Portuguese coach told Canal+ about the player he coached at Inter Milan.
"He's happy in Paris. I know because we're in contact, we're friends.
"With their financial potential, I don't think Paris will ever open the door for him to leave.
"Cavani is a very good player. But Paris paid a lot of money for him and he has an amazing contract."
While on the subject of PSG - who have been strongly linked with Chelsea's Eden Hazard - Mourinho insisted that his Belgian ace would be staying put.
"Eden is our lad. We want to build the team around him," he added.