Russia has attacked at least eight Ukrainian energy facilities since March 18 when Moscow says it halted such attacks, a senior Ukrainian presidential official said on Wednesday. Ihor Zhovkva, speaking on national television, also said that, contrary to Russian statements, no preconditions were discussed with U.S. officials as they agreed a Black Sea truce with Russia during talks in Saudi Arabia this week. The Kremlin said earlier that a number of conditions must be met before the Black Sea maritime security deal negotiated with the United States can be activated.