Russia's outgoing President Vladimir Putin hosted his U.S. counterpart George W. Bush on Sunday in his presidential residence in this Black Sea resort.

However, the two leaders failed to reach substantial agreements on vital issues ranging from missile shield plans to NATO expansion, but they did agree to continue dialogue to settle disputes and improve ties in a joint declaration issued after the one-day summit.

Russia's President Vladimir Putin (R) and U.S. President George W. Bush speak at a news conference at the Bocharov Ruchey presidential summer retreat at the Black Sea in Sochi April 6, 2008. The United States and Russia are interested in creating a system against potential missile threats, Bush and Putin said in a joint declaration on April 6, 2008.

Missle shield dilemma

The United States will "convince the experts that it's not against Russia," Bush told a press conference following the talks, in a bid in vain to eliminate Russia's worry and objection to its plans to deploy a third missile shield in Central Europe.

Two rounds of talks between top diplomats and defense officials of the two states have failed to make any breakthrough on the shield that consists of 10 missile interceptors in Poland and a radar station in the Czech Republic.

Washington says it will prevent potential missile attacks from Iran but Moscow says it will pose a threat to its national security.

Bush promised to share technology and information on the system to improve transparency and build up confidence.

Putin, however, urged Washington to do more. Focusing on "how those confidence-building and transparency measures will be implemented," he said he was glad that Russia's concerns "have been heard" in those talks and Sunday's meeting.