HALIFAX -- Senators from across Canada are coming together to press the federal and Nova Scotia governments for a response on a joint inquiry into the Nova Scotia mass shootings and related events.

In a letter addressed to Minister Bill Blair, David Lametti, Maryam Monsef, Mark Furey and Kelly Regan, 37 senators from across Canada call for a 'comprehensive, open and fully transparent process' to 'address the complexities of the massacre and answer the legitimate questions and concerns of Nova Scotians and Canadians.

The letter says the senators "remain troubled, that as of now, three months after the event, action on this has not been taken and no clear public explanation as to why has been provided."

This follows a pair of letters sent by Nova Scotian senators on June 7 and June 29 which called for a joint federal-provincial inquiry into the shootings, which claimed the lives of 22 people over April 18 and 19.

On June 18, Nova Scotia Justice Minister Mark Furey said most details of a joint federal-provincial inquiry had been finalized, and he was working out a time and location for an announcement with the federal government.

Two weeks later, Furey said he made a mistake when he suggested the terms of reference for the inquiry would be announced within days.

"I want to commit to the families that we understand their frustrations," said Furey on July 2. "We're working day and night to bring this together. There's legalities and technicalities that our legal teams are reviewing and finalizing in the drafting of relevant documents. That's what's taking the time."

Two weeks later, senators continue to press for details into the inquiry.

"The lack of an announcement of this inquiry is fueling speculation as to why it's not happening, and that resulting innuendo and gossip puts the public's trust in jeopardy- not only in those who strive their best to protect and serve, but also in those who are responsible for our public safety," reads the letter.

Since the attacks in northern and central Nova Scotia, the federal and provincial governments have faced increasing pressure to call an inquiry into one of the worst mass killings in Canadian history. Those demanding action have included family members, opposition politicians and more than 30 Dalhousie University law professors.

The call to action now has now expanded to inclue federal Attorney General and Justice Minister David Lametti, federal Minister for Women and Gender Equality Maryam Monsef and Nova Scotia’s Minister responsible for the Advisory Council on the Status of Women Act Kelly Regan, to "further highlight the importance of ensuring that a feminist lens is employed as part of this investigation".

In early June, Prime Minister Justin Trudeau committed to working with the province on setting up a larger review, while Blair told the Senate chamber on June 25 that work towards launching an inquiry was ongoing.