Not in RFC you can't. Which is fine, because you can't irrigate those squares either. Tundra is more useful in normal civilization. Fact is its awful territory, and if you wan the resources, you're just going to have to balloon out your cultural borders, or find the spots on the coast. You can get most if not all of the resources by building on the coast anyways.
If this is a bug, then I'd like to hear that confirmed, otherwise I think its just an intended restriction.