President Bush marked the 100th day of the war against terrorism Thursday by confronting directly one of its many unforeseen complexities: the rising tensions between Pakistan and India, two essential American allies in the anti-terror effort who are also nuclear-armed antagonists.

Bush called for a crackdown on the financial networks of two Pakistani terrorist groups, one of which he said was helping Al Qaeda acquire nuclear weapons. The other is one of two groups India accuses of leading last week's bloody attack on the Indian parliament in New Delhi.

Bush targeted the finances of Umma Tameer-e-Nau, a charity set up by a former Pakistani nuclear scientist that Bush said has provided money and information on nuclear weapons to Al Qaeda, the terrorist network led by Osama bin Laden. The president also singled out Lashkar-e-Taiba, a group that has repeatedly attacked India in a long-standing dispute over the Kashmir region claimed by both countries.

India has accused the government of Pakistan of backing Lashkar-e-Taiba, but Bush pointedly referred to the group as "a stateless sponsor of terrorism" in his Rose Garden announcement. That choice of words reflected the delicate path the administration must now walk between condemning the terror attack against the Indian parliament while continuing to bolster Pakistan as a key ally in the fight against bin Laden.

Indian officials are contemplating their response to the parliament attack, which left 14 people dead, including the five assailants, but Prime Minister Atal Behari Vajpayee, in a speech to parliament Wednesday, would not rule out military retaliation if diplomatic pressures failed to persuade Pakistan to crack down on the terrorist groups. Pakistan has demanded proof from India that any Pakistani militants were involved in the attack.

Secretary of State Colin Powell underscored the dangers of conflict between the two nations in an interview Thursday, noting that "it is a very volatile region, with two countries that are armed with all sorts of weapons," including nuclear weapons.

Powell said the Indians "are quite justified in going after those responsible and the organizations responsible, and to the extent that they have evidence that there's some state involvement, then that evidence should be brought forward."

"We are in close touch with the two sides," he said, "not to divert them from efforts to go after terrorists but to assist them to go after terrorists and see if we can keep the campaign against terrorists, and not a campaign of one state against another."

In announcing the crackdown on the Pakistani terrorist groups, Bush took care to express sympathy for the attack on the Indian parliament.

"The legislature of the world's largest democracy, a nation founded on the principles of freedom of speech, freedom of worship, was ruthlessly attacked," the president said. "If their mission had succeeded, they would have kidnapped and killed many of India's elected representatives."

Limited options

But Bush is limited in what action he can take against the two Pakistani groups because neither has financial assets in the United States, according to Treasury Secretary Paul O'Neill. The president has asked other nations to join in the effort to freeze the groups' assets and cut off the flow of money to them.

Bush said he would also take economic actions against any nations that aid the terrorist groups. Those nations would be prohibited from doing business in or with the U.S., he said.

"This is the 100th day of our campaign against global terrorism. And in those 100 days, we've accomplished much," Bush said. "We've built a broad international coalition against terror. We broke the Taliban's grip on Afghanistan. We took the war to the Al Qaeda terrorists. We're securing our airways. We're defending our homeland. And we're attacking the terrorists' international financial network."

The crackdown brings to 158 the number of organization and individuals identified by the U.S. as having financial ties to terrorist groups. So far, 142 countries have heeded the United States' call to freeze $33 million in terrorists' assets, Bush said.

Umma Tameer-e-Nau, or UTN, was founded by scientists formerly involved in Pakistan's nuclear weapons program who, like Pakistan itself, had close ties to both the Taliban regime in Afghanistan and bin Laden.

Its founder, Bashir-ud-Din Mahmood, has advocated providing Islamic nations and groups the enriched uranium and weapons-grade plutonium they would need to make bombs, according to the Bush administration.

Mahmood met earlier this year with bin Laden, the mastermind of the Sept. 11 terrorist attacks on New York and Washington, to advise him on developing a nuclear weapons program for Al Qaeda, officials said. Searches in Kabul turned up evidence that Umma Tameer-e-Nau had plans to kidnap a U.S. attache, and other documents outlined the basic physics of nuclear weapons.

The second group, Lashkar-e-Taiba, is the armed wing of the Pakistan-based religious organization Markaz-ud-Dawa-wal-Irshad, an anti-U.S. missionary organization formed in 1989, the Bush administration said.

Officials called it one of the three largest and best-trained groups fighting in Kashmir against India and charged that its operations have targeted civilians as well as Indian troops since 1993.

The administration said Lashkar-e-Taiba is suspected in eight attacks in August that killed nearly 100 people, most of them Hindus. The group also is suspected in the November 2000 kidnapping of six people, five of whom were killed.

Lashkar-e-Taiba collects donations from the Pakistani community in the Persian Gulf and United Kingdom, Islamic groups and Pakistani and Kashmiri businessmen, the administration said. The amount of the group's funding is unknown.

Bush hails anti-terror efforts

Though bin Laden remains on the loose, Bush hailed U.S. accomplishments in the war on terrorism over the last 100 days, including the creation of an international coalition to support the ongoing campaign.

The U.S., with its allies, has toppled the Taliban regime that ruled Afghanistan and was host to bin Laden. The U.S. also rescued aid workers being held by the Taliban and delivered 2.5 million humanitarian packages to starving Afghans, Bush recounted.

In sum, Bush said he was pleased with the progress and direction of the anti-terror campaign at the 100-day benchmark.

"I'm optimistic about the future of our struggle against terror," Bush said. "I know we've accomplished a lot so far, and we've got a lot more to do."