President George W. Bush and Senator John Kerry, his Democratic challenger in the November 2 election, both gave priority to nuclear non-proliferation towards the end of their televised debate here.

"There are terrorists trying to get their hands on that stuff today, and this president, I regret to say, has secured less nuclear material in the last two years since 9/11 than we did in the two years preceding 9/11."

"The president actually cut the money for it. You have to put the money into it and the funding and the leadership," Kerry said. "And part of that leadership is sending the right message to places like North Korea."

The Democrat said Bush was sending "mixed message" by spending hundreds of millions of dollars to research bunker-busting nuclear weapons.

"We're telling other people, you can't have nuclear weapons, but we're pursuing a new nuclear weapon we might even contemplate using," Kerry said, vowing to shut the program down if elected in November.

"We're going to make it clear to the world, we're serious about containing nuclear proliferation, and we're going to get the job of containing all of that nuclear material in Russia."

Bush said he agreed with Kerry the main security challenge was containing the spread of nuclear weapons and keeping them out of the hands of terrorists. He said his administration had boosted funding for this by 35 percent.

The president said Washington had spearheaded a "proliferation security initiative" involving more than 60 nations, had bust a Pakistani network and convinced Libya to disarm.

"We'll be implementing a missile defense system relatively quickly," he added, "and that another way to help deal with the threats that we face in the 21st century. My opponent is opposed to missile defenses."

The two clashed over efforts to persuade North Korea to renounce its nuclear weapons program and called for bilateral talks with Pyongyang as well as multi-party discussions also bringing in China, Japan, South Korea and Russia.

Bush responded: "I can't tell you how big a mistake I think that is to have bilateral talks with North Korea. That's precisely what (North Korean leader) Kim Jong-Il wants. It will cause the six-party talks to evaporate."

"We must have China's leverage on Kim Jong-Il besides ourselves. If you enter bilateral talks, they'll be happy to walk away from the table. I don't think that will work," Bush said.

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