The publicity-hungry Central Asian state of Kazakhstan on Wednesday hosted the first summit of the OSCE in over a decade, seeking to revamp the organisation's ability to react to security crises.

US Secretary of State Hillary Clinton and Russian President Dmitry Medvedev acknowledged the OSCE needed to play a more dynamic role but it remained unclear if the 56 member states could agree a strong action plan for its future.

"This summit is a sign of the rebirth of the organisation," Kazakh President Nursultan Nazarbayev, who championed the holding of the meeting, said as he declared the summit open in Kazakhstan's new capital Astana.

He called for the creation of a single security space spanning "the Atlantic, Pacific, Arctic and Indian Oceans," noting that some of the most serious threats to European security come from outside the continent.

The Organisation for Security and Cooperation in Europe grew out of the cooperation organisation that served as a forum for dialogue between East and West at the height of the Cold War.

The trans-Atlantic group aims to prevent conflicts through dialogue and help states recover from conflicts, although the goal sometimes becomes mired in disputes between members and its principle of operating on consensus.

The summit is the first time OSCE leaders have gathered since a meeting in Istanbul in 1999, a gap whose duration has raised questions about the group's capacities in the 21st century.

OSCE Secretary General Marc Perrin de Brichambaut admitted that in recent years some of its principles had "been neglected" and a "lack of confidence between member states" had limited its ability to respond to crises.

"The OSCE can only be as effective as you choose to make it," he told world leaders.

Clinton called for a "forward-looking framework for action" to implement the group's founding principles. "It can be effective only if participating states back its institutions and missions with political will."

Medvedev echoed Clinton's comments, telling the summit that it was necessary to modernise the OSCE. "Indeed the organisation has started to lose its potential. We need to state this clearly," he said.

The summit got underway amid some of the tightest security ever seen for such a meeting in the region, with 7,000 police deployed to ensure it passes without incident.

Many ordinary Astana residents have preferred to leave the city for the duration of the summit, with December 1-2 declared a public holiday in the capital and the area around the venue a no-go area for locals.

Nazarbayev has scored a major coup by attracting dozens of world leaders to his hitherto little-known capital, also including UN Secretary General Ban Ki-moon and Afghan President Hamid Karzai.

A senior diplomat close to the organisers, who asked not to be named, told AFP that Nazarbayev did "not appreciate" the decision of French President Nicolas Sarkozy to skip the summit and instead send his prime minister.

But the summit -- which coincides with Kazakhstan's 2010 chairmanship of the OSCE -- has also been criticised by some activists who say the country's dubious rights record made it a poor choice.

Nazarbayev -- president since independence from the Soviet Union -- enjoys the support of a rubber stamp parliament and has been accused of signing laws seen as restricting media and Internet freedoms.

New York-based watchdog Human Rights Watch described Kazakhstan's rights record as "stagnant" and said promises to improve media freedoms during its chairmanship had remained unfulfilled.

But after Kazakhstan's frosty reaction to the 2006 comedy hit film "Borat" about a fictional politically incorrect Kazakh journalist, the summit represents a chance for the country to project a shiny modern image.

Astana has grown exponentially since taking over from Almaty as Kazakh capital in 1997 and it boasts a skyline of modern buildings ranging from gigantic futurist structures to more stylish work by world architects.