Complex sentence: Polli had publicly stated in 2009 that he had denied requests by US intelligence agencies to do things that would be in violation Austrian law, stating in 2013 that it is "absurd and unnatural" for the German authorities to pretend not to have known anything.
Split into simpler sentences: Polli had publicly stated in 2009 that he had received requests from US intelligence agencies to do things that would be in violation of Austrian law, which Polli refused to allow. Polli, the former Austrian official, said in 2013 that it is "absurd and unnatural" for the German authorities to pretend not to have known anything.