In Moscow and Washington, Russian and US leaders expressed deep hopes that relations between their countries would improve. Then they offered fresh criticisms in spats over issues including missile defense, the future of Serbia's breakaway Kosovo province and Moscow's human rights record. The latest round of tense rhetoric offers a preview of the difficult climate that US President George W. Bush and his Russian counterpart Vladimir Putin will face when they meet at the Bush family compound in Kennebunkport, Maine, on July 1-2. Russian-US relations have worsened rapidly amid Moscow's criticism of the US missile defense plans and US complaints that the Kremlin was backsliding from its newfound democratic ways and strong-arming its ex-Soviet neighbors. Russian leaders offered fresh irritability Thursday after the United States refused to shelve plans for missile defense facilities in Central Europe while considering a proposal by Putin that the US use a Soviet-era radar in Azerbaijan instead of an installation to be built in the Czech Republic. The United States has said its missile defense system posed no threat to Russia's vast arsenal but was aimed at countering an emerging threat from Iran, which has been developing a ballistic missile program. Senior Russian officials warned Washington on Thursday that snubbing Putin's proposal would strengthen Russia's belief that it is the real target of the American system. Gen. Yuri Baluyevsky, chief of general staff of the Russian armed forces, said that with Iran posing no immediate missile threat, the aim of the planned US sites in Poland and the Czech Republic must clearly be aligned against Russia's nuclear arsenal. "That is a litmus test," Baluyevsky told reporters. "The entire world will see the true aim of this system." US officials insist that Central Europe is the ideal position from which to counter Iranian missiles with long-range interceptors. The chairman of the House of Representatives' Foreign Affairs Committee, Democratic Rep. Tom Lantos, said Thursday that US leaders believed Russia understands that the proposed system is not directed at Russia. Arguing that the system poses a threat has "diminished the credibility of the Russian government," he said. Lantos was speaking at an unusual meeting among lawmakers from the foreign affairs committees of the Russian Duma and the US House of Representatives, where Lantos also raised questions about Russia's human rights record and restrictions on press freedom. The comments came on the same day that Russian Foreign Minister Sergey Lavrov said the current state of the US-Russian relations was "alarming," and warned that Moscow would not accept lecturing from Washington. "Any format of relations with the United States other than equal partnership will be unacceptable to us," he said. On a conciliatory note, he added that Moscow was ready to improve relations with the United States if Washington would show more respect for Russia's interests. In another congressional event on Russian-US relations, lawmakers and a senior US diplomat also expressed unease about rising tensions. Only Russia has enough nuclear weapons "to wipe us out," Democratic Sen. Joseph Biden said in chairing a review of strained relations with Moscow by the Senate Foreign Relations Committee. In tandem with European leaders, Bush should make it clear that Russia has much to gain by cooperating with the United States on Iran's nuclear program, the future of Kosovo and on missile defense, Biden said. "Whatever our game plan has been - and I'm not convinced we've had one - it clearly isn't working," he said. In testimony to a US Senate panel, Assistant US Secretary of State for European and Eurasian Affairs, Daniel Fried, also criticized Russia Thursday for its refusal to back an international plan that would lead to the independence of Kosovo, a breakaway province of Serbia. "So far, Russia continues to reject any solution that is not approved by Serbia," Fried told Biden's committee, according to prepared remarks. He criticized suggestions by Russia that independence for Kosovo would set a precedent for other breakaway republics, including two in Georgia and one in Moldova, where Russia has previously shown sympathy for separatists. "We believe that such a position is destabilizing and reckless," Fried said. Fried said that the harsh criticism of the United States by Russian leaders in recent months was Moscow reasserting itself. "The world has witnessed a series of statements and initiatives from Russian officials in recent months that have left us puzzled and in some cases concerned," he said, according to prepared testimony. "In the view of many Russians, however, the European order that emerged in the 1990s was imposed on a weak, vulnerable Russia."