Russian President Vladimir Putin and Bulgarian Prime Minister Boyko Borissov have discussed on the phone joint projects in the energy sector, the Kremlin press service announced. The conversation was held on the initiative of the Bulgarian side. During the talks Putin and Borissov agreed to intensify cooperation in the framework of the Russian-Bulgarian intergovernmental commission on economic, scientific and technical cooperation. The conversation took place a day after the reply of European Commission President Jean-Claude Juncker on questions by the Bulgarian government regarding the implementation of energy projects, such as the Balkan gas hub, "South Stream", "Burgas-Alexandroupolis," as well as nuclear energy projects. Borissov pointed out that pipes for the construction of the South Stream project have already been stored in the ports of Burgas and Varna.