Pro-government Uzbek media outlets say the two officials discussed bilateral and regional issues.
Karimov reportedly told Boucher his visit would help improve relations "after a long break."
Ties between Tashkent and Washington soured after Karimov's government last year demanded that the Pentagon vacate an Uzbek military airbase it had been using since 2001 for operations in neighboring Afghanistan.
Following Tashkent's decision, the United States stepped up its criticism of Uzbek authorities for violently cracking down on a May 2005 popular uprising in the eastern city of Andijon.
Uzbekistan has in the past few months ordered that several U.S. nongovernmental organizations be closed down on various charges.
Boucher is due to fly to neighboring Kyrgyzstan later today.
(press-uz.info, Uzbek television)
Soldiers conducting the first-ever SCO joint antiterrorism exercises, held in Kazakhstan in August 2003 (TASS)
NATO'S EVIL TWIN? At an August 3 briefing at RFE/RL's Washington,D.C., office, Central Asia experts Richard Weitz and Daniel Kimmage discussed the emergence of the Shanghai Cooperation Organization (SCO), a multilateral body that comprises Russia, China, Kazakhstan, Kyrgyzstan, Tajikistan, and Uzbekistan. In addition, Iran, Pakistan, Mongolia, and Afghanistan have observer status in the organization.
LISTENListen to the entire briefing (about 75 minutes):
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