Milan vice-president Adriano Galliani has confirmed that the club has rejected an offer from Chelsea for Kaka.
Reports suggested that Kaka could be on his way to Stamford Bridge in a world record deal of 100 million Euros.
Kaka's agent fuelled rumors of a move to London by claiming that the player would be interested in a switch to Chelsea.
Milan moved quickly to put an end to the rumours by saying Kaka is not for sale and Galliani confirmed that Milan president Silvio Berlusconi rejected the mega bid from Chelsea.
"It's true that Chelsea made a conspicuous offer, but I will not say how much it was," Galliani told the Italian press.
"It is equally true that we said no. President Silvio Berlusconi rejected the chance to sell Kaka, just as he told Real Madrid no in 2001 for Andriy Shevchenko."
Galliani insists Kaka and Juventus target Clarence Seedorf will be staying with the Rossoneri for the new season. Seedorf is said to be disappointed that he has been told to give his number 10 shirt to newcomer Ronaldinho.
"Kaka is going nowhere and neither is Clarence Seedorf," added Galliani. "The fans can sleep easy."
Kaka admits he is unsure of his future claiming two clubs are chasing his services with Real Madrid thought to be rivalling Chelsea for the South American's signature.
"When I return to Italy I will know what's going to happen, but at the moment nothing is certain," said Kaka.
"There are two teams who are very interested in signing me, but now I do not want to talk about it.
"Until we return to Milan and know how things are, we cannot decide what happens with my future."