The economic performance of the region since independence has been mixed. It contains some of the largest reserves of natural resources in the world, but there are important difficulties in transporting them. Since it lies farther from the ocean than anywhere else in the world, and its southern borders lay closed for decades, the main trade routes and pipelines run through Russia. As a result, Russia still exerts more influence over the region than in any other former Soviet republics. Nevertheless, the rising energy importance of the Caspian Sea entails a great involvement in the region by the US. The former Soviet republics of the Caucasus now have their own US Special Envoy and inter-agency working groups. Former US Secretary of Energy Bill Richardson had claimed that "the Caspian region will hopefully save us US from total dependence on Middle East oil".