ASTANA, Kazakhstan -- A group uniting the U.S., Europe and Central Asian nations holds its first security summit in more than a decade Wednesday, with Afghanistan and international terrorism high on the agenda.

After the leak of hundreds of thousands of U.S. diplomatic cables, Secretary of State Hillary Rodham Clinton may also find herself uncomfortably in the spotlight as she meets with some leaders who were cited in unflattering diplomatic cables recently released by WikiLeaks.

The Organization for Security and Cooperation in Europe was born in the 1970s to nurture rapprochement between Cold War enemies. Holding its two-day summit in Astana, the gleaming new Kazakh capital rising from the sparsely populated northern steppes, was a coup for President Nursultan Nazarbayev.

Nazarbayev is eager to portray Kazakhstan as progressive and sophisticated, though critics say the country suppresses opposition, violates human rights and disregards Western standards of democracy.

"At the end of Kazakhstan's year at the helm of the leading world human rights organization, many observers are left looking at the significant work Astana still has to accomplish at home," U.S. Senator Benjamin Cardin, vice president of the OSCE's parliamentary assembly, said.

WikiLeaks' release of diplomatic cables may not help the country's image.

One note allegedly written by a U.S. diplomat in Astana details scenes of hard-drinking hedonism by several senior Kazakh ministers. The same report describes Nazarbayev as horse-obsessed and given to taking refuge from the often-frigid capital at a holiday home in the United Arab Emirates.

Other prospective conference delegates described less than flatteringly in the leaked cables include Italian Prime Minister Silvio Berlusconi and Russian President Dmitry Medvedev. That may leave Clinton with some explaining to do.

Kazakhstan insists it is a force for stability and prosperity in the region and that it has actively engaged with civil society to dispel the misgivings of those that would dismiss the country as unresponsive and unaccountable.

But a group of activists from nearby Turkmenistan complained that the Kazakh government had denied it visas to attend a parallel event in Astana.

"The authorities of Turkmenistan and Kazakhstan exerted as much force as they could to block our arrival in Astana," the Vienna-based Turkmen Initiative for Human Rights said.

Delegates are also likely to look with concern at another of Kazakhstan's southern neighbors, Kyrgyzstan, which has been wracked this year by waves of political and ethnic violence. Kyrgyzstan is also an OSCE member.

An explosion rocked the center of Kyrgyzstan's capital, Bishkek, on Tuesday, slightly wounding two police officers, a day after security forces battled Islamic militants in a restive southern city.

Security officials said the attacks appear to be part of a systematic attempt to foment turbulence in the Central Asian nation.