The head of the Quebec City mosque where six men were killed in a shooting almost two years ago wants the province to tighten up controls over who has access to firearms.

In a letter to Premier Francois Legault made public Monday, Boufeldja Benabdallah identified a weakness when it comes to verifying people who have mental health problems.

He said that the gunman Alexandre Bissonnette, who will be sentenced Feb. 8 after pleading guilty to six counts of first-degree murder, had mental issues but provincial police did not check.

Benabdallah said that when Bissonnette applied for his permit, he did not acknowledge on the form that he had experienced periods of depression, and his family did not report it to authorities.

He added that if police had been alerted to Bissonnette's mental problems and an inquiry revealed a threat to public safety, they could have made a preventive seizure of the firearms in his possession.

Benabdallah said that since the abolition of the federal firearms registry in Quebec in 2015, it has not been possible for police to know which firearms a permit holder owns.

He noted that Bissonnette acquired unrestricted firearms, including a CSA-VZ-58 assault weapon, which jammed during his Jan. 29, 2017 attack on the mosque.

Quebec passed a law creating a long gun registry in 2016 and has given owners until Jan. 29 to register their firearms or face penalties of up to $5,000. As of Sunday, 342,359 firearms had been registered, less than one-quarter of the 1.6 million long guns that the government estimates are owned by Quebecers.

Asked Monday about Benabdallah's request, Legault said he's not planning any changes to the provincial law. "For now, there is nothing more planned than what actually exists," Legault said in Paris, where he is on an official visit.

But Benabdallah said in a phone interview that he isn't asking Legault for more legislation -- just better screening.

"We're simply asking him to tighten up the verifications before the registering (of a firearm) to ensure that such a person is in a good state of mind and doesn't have any prior history and doesn't have periods of depression," he said.

Benabdallah is also worried about the influence of the pro-gun lobby and has urged Legault not to delay implementation of the law. "We want that to be applied, because there's a lobby on the other side that's telling him not to apply it," he said. "There shouldn't be any delay on that."

Pro-gun activist Guy Morin has called on the public to "wait until the last minute" to comply with the law. He said in December that his hope was either the registry would be abolished or so few people would register "that it cannot be enforced."

Canadian law classifies guns in three categories. Prohibited guns such as automatics and restricted guns such as handguns must be registered with the RCMP. Long guns -- rifles and shotguns that are mainly used for hunting and sport shooting -- no longer need to be registered in Canada, except in Quebec.