If I'm reading it right, Coleman is threatening him with perjury, if he lied. I'd say that's getting tough.
I'd say that's talking tentatively in political double speak, like the sanctimonious little twit Norm Coleman really is.
Even if he did commit perjury (which is almost a certainty), the fact that he's a duly elected leader of the government of an ally means realistically that we could never lay a finger on the SOB.
The best that we could hope for would be an international prosecution, but that will never happen. In a more sane world, he would be prosecuted within his own country, but that's not going to happen either.