OTTAWA—The Harper government says it will extend the life of its fleet of CF-18 fighters.

A spokeswoman for Defence Minister Rob Nicholson says the jets are an important component of the country’s defence and will be updated to keep them flying until 2025.

Johanna Quinney says the air force needs a fighter strike capability, but also aircraft that are capable of fulfilling a variety of other missions, such as patrol and air-to-air interception.

Four CF-18s are taking are taking part in air policing missions over the Baltic states as part of NATO’s efforts to reassure eastern European allies rattled by Russia’s annexation of Crimea and interference in Ukraine.

The federal cabinet is also considering a deployment as part of the wider air campaign against the Islamic State in Syria and the Levant.

Quinney did not say how much the government intends to spend on the upgrade, which would focus on strengthening the airframes and overall wing structure, or how it affects the decision whether to proceed with the F-35 purchase.