Prime Minister Stephen Harper says his government will spend $5.8 billion on federal infrastructure improvements, including $500 million for on-reserve schools.

At least some of the money has been previously announced. The $500 million for First Nations infrastructure was included in the 2014 federal budget, the Prime Minister's Office confirmed to CBC News.

"We are ahead of track in terms of balancing the federal budget next year," said Harper, who made the announcement at a research facility in London, Ont.

"This gives us flexibility to make additional investments ahead of schedule in a wide range of necessary federal infrastructure projects."

The Assembly of First Nations said $500 million falls short of "the urgent need for resources to build and repair First Nations schools."

“We will continue to press the federal government for a real investment in First Nations education and re-engaging on a new approach for success based on First Nations control of First Nations education," said Morley Googoo, AFN regional chief for Nova Scotia and Newfoundland, in a written statement.

The AFN called on the federal government to "reaffirm" its commitment to the $1.9 billion in funding for First Nations education that the prime minister announced last February.

$2.8B for historic sites, parks and conservation

The lion's share of the spending announced today – $2.8 billion – will go for improvements to historic sites, national parks and national marine conservation areas.

But NDP infrastructure critic Marjolaine Boutin-Sweet said she was reluctant to comment on the announcement because she didn't know if the funding was new or whether it was a "re-announcement."

"It wouldn't be the first time," she said, adding that she would have to see the details first. "We'll have to know exactly what we're doing with that money, rather than just an announcement."

Liberal deputy leader Ralph Goodale told CBC News in a telephone interview if all of today's $5.8 billion in federal funding was new, "the country would be back into a deficit."

"It's re-packaging or rebundling," he said of today's announcement.

The Conservative government has forecast a slim $1.9-billion surplus for next year.

The projection was smaller than expected due to low oil prices and Ottawa's recent commitment of billions of dollars for a tableau of savings measures aimed at families.

Harper also earmarked $452 million to improve Canadian Forces facilities, $440 million for replacing border infrastructure and about $400 million to upgrade and build federal government buildings.

Federally owned and operated airports and Via Rail will get $204 million for improvements, while $191 million will go to renew and repair heritage sites and museums.

Money is also going to federal labs and research facilities and small-craft harbours.

The Canadian Coast Guard and Fisheries and Oceans Canada will get $183 million to repair existing vessels and buy new ones.

With files from CBC News