LIMA, Peru, March 23 — President Bush pledged today to help President Alejandro Toledo of
Peru fight Marxist guerrillas on Peru's border with Colombia, saying that countering violence and
drug trafficking in the Andes was crucial to maintaining the stability of the region.

"We will help him in this effort," Mr. Bush said at a joint news conference with Mr. Toledo at the
Presidential Palace, only three days after a car bomb killed nine Peruvians outside the American Embassy.
"That's part of the reason why I'm here."

Mr. Bush also reaffirmed his commitment to an Andean trade agreement, vital to the region but stalled in
the United States Senate, and announced that the Peace Corps would return to Peru after an absence of
nearly three decades.

Mr. Bush, the first sitting American president to visit Peru, arrived here this afternoon in 90-degree heat
and in an atmosphere of extraordinarily tight security. American and Peruvian officials said that the huge
car bomb that exploded on Wednesday night, wounding 30, could be the work of the Shining Path, a
Maoist rebel group that carried out a series of terror attacks here in the 1990's.

As Mr. Bush and Mr. Toledo walked arm in arm into the Presidential Palace, traffic remained barred
from the historic heart of Lima, a 10-square-block area of Colonial mansions and palaces, while armored
vehicles and police in riot gear patrolled the streets. All commercial flights and even hang-gliding, a
popular sport over the cliffs jutting out into the Pacific, were banned during the president's visit. Several
square blocks around Mr. Bush's hotel, the Marriott in the affluent beachfront area of Miraflores, were
closed to both pedestrians and cars. Just hours before Mr. Bush arrived, police fired tear gas into dozens
of anti-American demonstrators near the Palace of Justice.

Mr. Bush was greeted with a 21-gun salute at the Jorez Chavez International Airport, then went to the
palace for talks with Mr. Toledo, whose popularity is plummeting, even though he is trying to reform his
habits of frequenting trendy nightspots and showing up late for work.

The two leaders said that they discussed trade, drug trafficking and terrorism, particularly the intensifying
war between Marxist guerrillas and the government of Colombia, Peru's neighbor to the north.
Colombian government officials say that the guerrillas, the Revolutionary Armed Forces of Colombia, or
FARC, are increasingly crossing into bordering states, including Peru. But Mr. Toledo went to some
length today to say that was not true.

"The evidence that we have indicates that there is no transfer of the FARC into Peru," Mr. Toledo said at
the foot of a marble stairway in the neo-Baroque splendor of the Presidential Palace. But Mr. Toledo said
that as a precaution he had moved military bases from the border of Ecuador to the border of Colombia.

Late this week, the Bush administration asked Congress to lift restrictions on military aid to Colombia to
help the government fight the rebels. If approved by Congress, the change would open a new front in
Colombia for American military trainers by involving the United States directly in the fight. Until now,
Congress has restricted the use of American aid to Colombia, which has totaled nearly $2 billion in
recent years, to fighting drug trafficking.

The Peruvian press has speculated in recent days about a possible American military operation on the
Peru side of the border with Colombia, a subject that neither leader addressed in the news conference,
and which Mr. Bush sidestepped during an interview at the White House last week with Latin American
journalists. Asked if the United States had plans for a military base in the Amazon jungle on Peru's
border to fight drug trafficking, Mr. Bush replied, "I can't get too specific about placements. Let me just
put it to you this way: We're willing to cooperate to do as effective a job as we can on interdicting."

Mr. Bush and Mr. Toledo also met here today with the leaders of three other Andean nations, Colombia,
Bolivia and Ecuador, to discuss the Andean Trade Preferences Act, a law that for the past decade has
lowered tariffs for 6,000 products from the region. But the pact expired in December and the Senate
failed to renew it, greatly irritating Mr. Bush. "It is stuck in the Senate," he said at the news conference,
"and I urge the Senate to act."

After the meeting between Mr. Bush and the four Andean leaders, a White House spokesman cheerfully
told reporters that one of the leaders had complained about the Senate's slowness on the trade deal.
"The Senate is mañana-ing this to death," Sean McCormack, the spokesman, quoted the leader as saying.
Mr. McCormack would not say which official had turned the Spanish word for tomorrow into a verb.

Earlier in the day, the president of Bolivia, Jorge Quiroga, told reporters that his country had dramatically
reduced the acreage of fields of coca, the leaf used to make cocaine, and deserved trade preferences from
the United States. "We have carried out this titanic job, reducing drug trafficking," Mr. Quiroga said.
"That merits an opening of markets."

Mr. Bush also said that he had not decided whether to resume drug surveillance flights over Peru, a joint
program of the Peruvian Air Force and the C.I.A. The flights were suspended last April after a Peruvian
military jet mistakenly shot down a missionary flight, killing a 35-year-old American woman, Veronica
Bowers, and her infant daughter.

"We are reviewing all avenues toward an effective policy of interdiction," Mr. Bush said. "As you know,
we had a terrible situation where a young mom and her daughter lost their life. That caused us to step
back to take a look at our policy."

Before Bush left Washington, the White House announced that the administration would compensate the
Bowers family.

Mr. Bush also said that the United States — which recently announced that it would triple, to more than
$150 million, its aid to Peru to fight drug trafficking — bore some responsibility for the region's drug problems.

"The best thing that America needs to do is reduce demand for drugs," Mr. Bush said.
"We've got to do a better job of convincing our own country to quit using them."