Canada’s five big shipyards will slug it out over the next two years to become the preferred builders of a new fleet of combat and civilian ships, federal ministers said Thursday.

Only two yards will construct the estimated 28 big ships the federal government wants to acquire over the next three decades. The remaining companies will then bid on small vessel contracts, as well as repair and refit jobs.

The plan is the centrepiece of the federal government’s shipbuilding strategy, with an estimated $35 billion in navy and coast guard vessel purchases.

To become a preferred “strategic” builder, companies must promise millions of dollars in infrastructure investment as well as job commitments.

“The five shipyards that are going to compete for these two opportunities for long-term contracts with the government of Canada will have to put some skin in the game and show us how they’re going to create jobs and invest in the maritime sector,” Public Works Minister Rona Ambrose said.

“The competitive process begins today.”

Critics warned the strategy could pit both coasts against one another and could also be costly for industry as the notoriously cut-throat companies climb over each other for one of the coveted spots.