1) his move toward the renationalization of Russian oil goes against one of the main priorities of US policy-makers, i.e., the opening up of the entire world to US investment, especially the opening up of oil resources for US control.
2) it is standard for the US elite to have some criticisms of even their closest allies (here, Putin), as a way to pressure them to come even closer to full obedience.
please correct me if I am wrong.
JD