Most of the interclubs were "entry" level bikes and in most model years came with what appears hi tensile steel tubing.

Gitane USA - Interclub

Interesting. My bike has a pretty lugs with windows and gold pinstriping; the rear brake bridge has nice reinforcements. I also have a mid 70s Peugeot PR 10 which is a similar level of bike (reynolds 531 DB main frame) and the workmanship is more utilitarian than the Gitane.