​A re-elected Conservative government could end up approving the construction of as few as 11 warships to replace the navy's frigates, despite committing to 15 combat vessels under their $36 billion national shipbuilding program.

Conservative candidate Jason Kenney, the defence minister, offered that update on Friday in Dartmouth, which is now cutting steel on the government's long-promised Arctic Offshore Patrol Ships.

Once those light icebreakers are completed, Irving Shipbuilding — the federal government's go-to contractor for combat vessels — is expected to begin construction of the more technically complex Canadian Surface Combatant ships, which are intended to replace not only the existing frigates but also the navy's command and control destroyers.

Kenney says the government intends to build anywhere between 11 and 15 frigate replacements.

Kenney says the program is still years down the road and a future government will have to decide how many ships to build — or whether to put in more money.

But he indicated there might have to be "trade-offs" and applauded the navy for considering the idea of reusing parts from the frigates on the new warships whenever they arrive.