For federal government employees across Canada, Monday, Sept. 19 will be a holiday and a national day of mourning as Queen Elizabeth II鈥檚 funeral takes place in the United Kingdom.

"We have ... chosen to move forward with a federal holiday on Monday," Prime Minister Justin Trudeau said at a news conference Tuesday morning in New Brunswick.

"We will be working with the provinces and the territories to try and see that we're aligned on this. There are still a few details to be worked out, but declaring an opportunity for Canadians to mourn on Monday is going to be important."

Some provinces and territories, including all four Atlantic provinces, Manitoba, British Columbia, Nunavut and the Yukon are also designating Monday a holiday for some workers.

This means a variety of federal, provincial and other services across the country will be unavailable Monday as workers pay their respects to the late Queen.

Here is what will be open and closed in Canada on Sept. 19.

NATIONWIDE

Across the country, any service staffed by federal employees will be unavailable as those employees observe the one-time holiday. This includes all Canada Services offices. Service Canada appointments are being rescheduled/postponed and that some community SIN clinics will go ahead as scheduled.

will also observe the holiday, meaning there will be no mail delivery and Canada Post offices will be closed on Sept. 19.

Banks and other federally regulated services and businesses will remain open, unless they opt to close. While Sept. 19 is not a statutory holiday, businesses anywhere in the country may still choose to recognize the day of mourning, so it鈥檚 best to check ahead and confirm if you鈥檙e not sure whether one will be open or not.

THE YUKON

All public schools in the territory, from kindergarten through post-secondary, will close. Public-facing territorial services and offices will also close.

The is encouraging private sector employers and organizations and other levels of government to 鈥渙bserve the National Day of Mourning in ways that are suitable for their employees and operations,鈥� so some municipal services and private businesses may also opt to close.

BRITISH COLUMBIA

Provincial and most Crown corporations in British Columbia will be closed, along with all public schools from kindergarten through post-secondary.

Premier John Horgan said the province is encouraging private-sector employers "to find a way to recognize or reflect on the day in a way that is appropriate for their employees.''

MANITOBA

All non-essential and offices, including Provincial Services locations, will be closed for the day.

Schools, child-care facilities and the health-care system will continue to operate as usual. The holiday does not apply to private-sector businesses and employers, but some may choose to close.

NUNAVUT

All offices and agencies will be closed on Monday.

The government has not announced any public schools in the territory will close, but it is inviting private businesses and employers to close in observance of the holiday, if they choose to.

ATLANTIC CANADA

Provincial government offices and public schools in Nova Scotia, New Brunswick, Prince Edward Island and Newfoundland and Labrador, as will all provincially regulated services.

Regulated child care in Nova Scotia will also be closed, but health-care services, appointments and procedures will go ahead as scheduled.

In , New Brunswick, and Newfoundland and Labrador, the holiday will be optional for private sector businesses and employers, so some businesses may choose to close.

With files from CTVNews.ca鈥檚 Spencer Van Dyk and CTVNewsAtlantic.ca鈥檚 Stephen Wentzell