The local council had provisionally approved plans for building a $5 million mosque 400 metres from the world famous tourist attraction, which is visited by more than one million persons each year, the Guardian reported on Wednesday.
Hundreds of residents took part in a protest last weekend organised by the no-mosque campaign and organisers said they gathered more than 2,000 signatures on a petition calling for a referendum on the issue.
The right-wing Forza Italia party, which was leading the campaign, claimed that a majority of the city's 90,000 persons opposed the building of the mosque.
Gianluca Gambini, a local Forza Italia politician, told the local media: "It's not just that it would be built in the wrong location, just 400 metres from the Leaning Tower, but also because people know that mosques are places where there is a risk of radicalisation."
Daniela Santanche, a Forza Italia MP who joined the protest, said: "Today we are at war, whether you like it or not, and we have to fight it with whatever we have. Mosques should be closed, not opened, because they are not places of worship, but places that preach hatred."
The Mayor of Pisa, Marco Filippeschi said any move to block construction of the mosque would contravene freedom of worship, which is enshrined in the Italian Constitution.
"For 20 years, Muslims from Pisa have been coming together in a small mosque in the centre of the town and no one has ever protested," Filippeschi said.
"Not one cent will be spent by the council administration to build the mosque," he added.
Pisa's Muslim population has been increased by recent migration from north Africa and Bangladesh.
Izzedin Elzir, the president of the Union of Islamic Communities in Italy, said a referendum on the mosque would be unconstitutional and threaten Muslims' religious freedom.
"Our rights should be protected. This campaign is based on prejudice and opposition generated by politicians who want to win votes by exploiting fear after the recent attacks in France, Belgium and Germany. They need to take responsibility for fanning the flames of prejudice and creating panic," the Guardian quoted Elzir as saying to the Religion News Service.
Construction of the 57-metre (187ft) Leaning Tower of Pisa began in 1173 and took about 200 years to complete. The tower started sinking soon after construction began. Restoration work carried out between 1990 and 2001 corrected the angle of tilt from 5.5 degrees to 3.99 degrees.
