The regulations, which have become known as the "anti-mosque" law, were approved by the right-wing dominated regional council at the end of January.
Amid an outcry over what critics see as a blatantly discriminatory move, Prime Minister Matteo Renzi's centre-left government has decided to refer the new rules to the Constitutional Court for review.
Under the regulations, anyone seeking to build a new place of worship for a religion not officially recognized by the state would be subject to an extensive list of special restrictions ranging from the size of associated parking facilities to the outward appearance of the buildings, as well as having to clear a string of new bureaucratic hurdles.
Since Islam is the only major religion not recognized by the Italian state, the new rules have been seen as being specifically targeted at Italy's one million plus Muslims.
Critics say the legislation breaches Italy's constitution on several grounds and is bound to be overturned by the Constitutional Court.
Issues judges will consider are expected to include whether the new measures breach guarantees of religious freedom, whether the region has exceeded its power by redrawing the relationship between state and religion, and whether the new law leaves too much to the discretion of local mayors.
Under one provision of the Lombardy law, local mayors who were unhappy about the construction of a new mosque could seek to organize a local referendum before granting or refusing permission.
It also stipulates that the dimensions and architectural proportions of any new place of worship should be in keeping with Lombardy's landscape – a requirement that appears custom-written to block any plans involving minarets.
The Renzi government's decision to block Lombardy's plans prompted a scathing response from Matteo Salvini, the overtly anti-Islam leader of the far-right Northern League.
"Renzi and (Interior Minister) Alfano – here are the new Imams," Salvini wrote on his Facebook page. The League is the dominant force in the coalition that runs the Lombardy region.
Purpose-built mosques are rare in Italy, although Rome is home to the largest one in Europe.
Generally, most Muslims living or visiting Italy pray in adapted buildings rented from local authorities or private landlords.