Speaking at a news conference after a Tuesday cabinet meeting, the PM said access to obtaining a Danish residence permit for foreign missionaries has been too easy up until now.
"That is why we now put forward new requirements for residing in the country, like the demand that imams and others have an education and that they be financially self-sufficient."
The proposed changes, which parliament is expected to rapidly pass into law, are part of a deal reached last September.
New immigration rules
The new rules were initially agreed between the Liberal-Conservative government, its far-right ally, the Danish People's Party (DPP), and the opposition Social Democrats.
They are designed, in part, to deter Islamic clerics from establishing bases in Denmark and clip the wings of those already living in the tiny country.
The DPP confirmed the immigration changes were aimed to curb the activities of imams.
"In theory, these rules concern all clerics from all religions. But in practice, they target the imams," DPP spokesman Peter Skaarup told journalists in September.
The government also said on Tuesday it intended to beef up measures against people who helped hide rejected asylum seekers so they would not be expelled from the country.
"In theory, these rules concern all clerics from all religions. But in practice, they target the imams"
"The fines inflicted on those who break the law by hiding refugees have been insufficient. We therefore propose more severe sanctions against the offenders," Rasmussen said.
The new restrictive laws could also affect refugees who have been given asylum in Denmark – allowing the loss of residence permits for those who decide to return to their home countries on holiday.
The government also proposed a 10-year "quarantine period" for any refugees convicted of violence against a former wife or girlfriend, before they can bring their current spouse to Denmark as part of the country's family reunification programme.
The Muslim faith is Denmark's second largest religion after the Lutheran Protestant Church, which is actively followed by four-fifths of the country's population of 5.3 million.
Muslims account for 3% of the population, about 170,000 people.