VIENNA (Reuters) - The election of Barack Obama as U.S. president has given crucial impetus toward implementing the Comprehensive Nuclear Test Ban Treaty more than a decade after it was negotiated, pact officials said on Wednesday.

The global treaty, which prohibits all nuclear explosions, cannot enter into force before it is ratified by all 44 states listed in an annex that took part in the 1996 negotiations and have nuclear power or research reactors.

Nine of the 44 have not ratified the pact -- Iran, Israel, North Korea, Indonesia, Egypt, India, Pakistan, China and the United States, where the administration of outgoing President George W. Bush was wary of multilateral commitments restraining its security options.

But Obama said in his campaign he aimed to secure U.S. Senate ratification as quickly as possible, a pledge which, if honored, treaty administrators said could do much to bring the other key holdouts on board.

Tibor Toth, the treaty organization’s executive secretary, said at the close of a meeting of 180 member states that Obama’s commitment meant “we are turning the corner in a wider political sense ... and the nine remaining dominoes should fall.”

The meeting’s chairman, Hans Lundborg, estimated that could now happen within two years, although Obama -- who takes office on January 20 -- admittedly would be preoccupied initially with the world financial crisis which originated in the United States.

“We have political momentum after the U.S. election ... and Obama’s message is extremely crucial to us, and for other countries to pick up that message,” Lundborg said.

Obama also has said he would encourage other states, most notably regional nuclear rivals India and Pakistan, to embrace the treaty.

Indonesia said recently it was undertaking “serious preparations” for ratification of the test ban.

Other ratification laggards have had concerns about limiting their strategic choices or doubts about the treaty’s verification mechanisms.

The United States, China, India, Pakistan are declared nuclear weapons powers, while Israel is widely assumed to be one but never confirmed this.

Stalinist North Korea tested a nuclear device in 2006 and agreed a year later to a disarmament-for-aid accord with five powers but the deal has faltered in disputes over verification.

Iran denies Western suspicions that it is secretly trying to build nuclear weapons, insisting its uranium enrichment programme is for electricity generation only.