By the year 2015, as many as 100 Chinese nuclear missiles could be aimed at the continental United States, as could long-range nukes in Iran and North Korea, a new CIA report said.

The long-range missiles, capable of hitting the U.S., are part of China's strategy of maintaining a nuclear deterrent against America with a larger, mobile force, "Foreign Missile Developments and the Ballistic Missile Threat Through 2015," reported Wednesday.

Many of China's missiles will be kept on hard-to-find mobile launchers, the report predicted, and the emphasis on more long-range missiles is being spurred by President Bush's missile-defense program.

Currently, China has about 20 silos with CSS-4 nuclear ICBMs that are capable of reaching the United States, according to the report. Another dozen nuclear missiles can reach targets in Russia and Asia.

China also has a few medium-range submarine-launched ballistic missiles, and probably only one submarine from which to launch them.

The Chinese military is developing three new missile systems, two truck-launched missiles and a new submarine-launched missile, all of which could be fielded by 2010, the report stated. The Chinese may also be able to mount multiple-independent re-entry vehicles — MIRVs — on its older silo-based missiles. These enable a single missile to launch warheads at several targets, vastly increasing the missile's potential damage.

The report is an unclassified summary of a National Intelligence Estimate, which draws together information and analyses from the CIA and other U.S. intelligence agencies about foreign countries' missile development programs.

In Beijing, Foreign Ministry spokesman Sun Yuxi said Thursday that China would strengthen its national defense "in accordance with its own needs."

He vaguely dismissed the CIA report.

"I have no details on the specific report," he said, "but I think such matters are merely baseless speculation."

One hundred missiles would be too many for most of the missile defense systems envisioned by the Pentagon, ensuring that China has a deterrent against U.S. entry into a fight over Taiwan.

China also is expanding its short-range ballistic missile force, and will probably have several hundred by 2005, the report said. These are armed with conventional warheads that could be used to bombard Taiwan from the Chinese mainland.

The Bush administration has used assessments like the CIA report to justify U.S. plans for multibillion-dollar missile defense systems capable of shooting down a limited ICBM attack on the continental United States.

Last month, President Bush argued the threat of missile attack by terrorists is reason for the United States to pull out of the 1972 Anti-Ballistic Missile treaty with Russia.

"I have concluded the ABM treaty hinders our government's ability to develop ways to protect our people from future terrorist or rogue state missile attacks," he said.

While U.S. officials insist the missile defense program is to defeat strikes by North Korea and other "rogue" nations, some of those proposed defenses might be sufficient to shoot down all 20 Chinese ICBMs.

Analysts say that having a missile defense system would give the U.S. more freedom to go to war over Taiwan, should China invade it.

But the new report said terrorists aren't expected to employ long-range missiles to deliver nuclear and other weapons of mass destruction on the United States.

"Ships, trucks, airplanes and other means may be used," it said. Hostile countries may employ similar means, it said.

These delivery methods can be used covertly, are cheaper and more accurate than non-U.S. ICBMs, and avoid any missile defenses, the report said.

Arguing for such a system, Bush suggested earlier this year that a rogue state might not be restrained by the fear of nuclear annihilation as the Soviet Union was.

North Korea, meanwhile, has halted missile flight-testing until at least 2003, although it continues to develop the Taepo Dong-2, a two-stage missile that would be capable of reaching parts of the western United States. North Korea also probably has one or two nuclear weapons that could be mounted on those missiles, the report said.

Iran, meanwhile, might be able to test a long-range missile around 2005, but more likely won't have the capability to do so until 2010, the report said.

The report reflects some differences of opinion between U.S. intelligence agencies, with one unidentified agency arguing that Iran won't be able to test missiles able to reach the U.S. mainland even by 2015. Its projections also assume each country's political direction will not change significantly during the next 13 years.

Iran will rely on foreign assistance from Russia, China and North Korea to complete its missile program, the report said.

Russia's strategic missile force will continue to get smaller, with or without arms control agreements, but Russia will still have far and away the largest nuclear missile inventory capable of hitting the United States, the report said.

The Associated Press contributed to this report.