* New "tone" of Obama credited with breaking deadlock
* U.S., France agree to review of old disarmament pledges
UNITED NATIONS, May 6 (Reuters) - Delegates meeting on the 1970 Non-Proliferation Treaty struck their first agreement on the anti-nuclear arms pact in a decade on Wednesday, which diplomats said was largely due to U.S. President Barack Obama.
Three days into a two-week meeting on the landmark arms control agreement, delegates from its 189 signatories agreed on an agenda for a major conference next year, where member states hope to adopt an action plan to overhaul the treaty.
"Amazing," Ambassador John Duncan, head of the British delegation, wrote on a website he updates regularly. "We just agreed the agenda for the 2010 review conference. It may seem boring but we haven't done so for a decade."
Other diplomats described the agreement as modest but significant, because member states have been unable even to agree on what they should talk about for 10 years. They said Obama's new tone was probably the decisive factor.
NPT signatories have tried for years to overcome sharp divisions, with developing countries complaining that the big nuclear powers have reneged on obligations to disarm while denying them access to nuclear technology.
The last NPT review conference in 2005 descended into procedural bickering and accomplished nothing. Washington tried to focus attention on the Iranian and North Korean nuclear programs, while Iran condemned the failure to disarm and Egypt pointed to Israel's presumed nuclear weapons.
The agenda agreed on Wednesday includes a review of disarmament commitments made by the United States, Britain, France, China and Russia in 1995 and 2000. It also includes a discussion of "nuclear-weapons-free-zones" -- which diplomats said would mainly be about Israel's presumed nuclear arsenal.
The disarmament commitments have been very divisive in recent years after former President George W. Bush decided he was not bound by those pledges and insisted they be dropped from the agenda. The French supported that position.
"The Obama administration did an about-face and agreed to bring those commitments back on the agenda," a diplomat said, asking not to be be named. "The French were still trying to block it but gave in overnight when they realized they were alone and isolated."
Western diplomats said they were worried that Egypt and Iran would keep trying to divide the conference by focusing on Israel. But they said they were pleased that Tehran and Cairo were not finding it so easy now to divide signatories.
Iran denies Western charges that it wants atomic weapons.
"Huge obstacles remain, but the clear change of tone coming from the Obama administration has changed the equation," said one Western diplomat involved in the talks. "The U.S. is now willing to engage on disarmament. It's willing to engage with Iran. It mentions Israel. That's all new and it's helping."
U.S. Assistant Secretary of State Rose Gottemoeller read a message from Obama to the delegates on Tuesday in which he reiterated his vow to take new disarmament steps while urging delegations to bridge differences on strengthening the NPT.
Although she did not mention Iran in her speech, Gottemoeller said Washington wanted Israel, India and Pakistan to join the NPT and North Korea, which pulled out of it in 2003 and tested a nuclear device in 2006, to return to the pact.
Israel on Wednesday dismissed Gottemoeller's comments. (Editing by Alan Elsner)
Our Standards: The Thomson Reuters Trust Principles.