The Serie A outfit were expected to move away from the iconic venue to a new home, but mayor Luigi de Magistris has revealed that an agreement has been reached to transform Stadio San Paolo.
Napoli president Aurelio De Laurentiis is now due to put forward funds to confirm the club's commitment to the project.
De Magistris told Radio Kiss Kiss Napoli on Monday: "I can confirm that we are on the right track.
"On Friday we sent the necessary documentation to Napoli so that they know the exact fees to be paid.
"Without this there would need to be a delay in proceedings. Napoli will play at San Paolo and there will be a commitment to redeveloping the entire stadium.
"We have now reached an agreement, thanks to De Laurentiis making himself available. He will pay the amount due before we move on to discuss the next steps.
"Sometimes things are not easy to sort out. Things will begin to move forward immediately. Once the payment has been received we can sign for the plan to go ahead.
"I would like for the research to be done before the end of the year, at which point there will be a commitment to putting the necessary money in to fund the building of the stadium.
"Will there be an athletics track? There is a commitment to create a project, I will trust those who have designed the most beautiful stadiums.
"I want a project worthy of football and of the city. There will be a debate to discuss the issue, at the moment the most important thing is that we have reached an agreement.
"We may decide to move the stands forward, but we may also decide to leave the athletics track in place."
