Buoyed by high oil prices, Russia finds itself embroiled in a number of disputes with foreign firms looking to tap its underdeveloped oil fields and with its neighbors that grew used to subsidized ga…

Backgrounder: Lingering resentment over NATO’s expansion has strained U.S.-Russia relations.

The flow of Russian conventional weapons to Iran—notably sophisticated surface-to-air defense missiles—has increased markedly of late, complicating U.S.-led efforts to tamp Tehran’s nuclear ambitions.

As the world struggles to find a formula for dealing with suspicious nuclear developments in Iran , Russian diplomats have been holding bilateral talks with Iranian officials on a proposal they say c…