Secretary of State George P. Shultz, seeking to "reaffirm the partnership" with the Philippines forged in the heady triumph of "people power," said today that the United States can provide more rapid assistance to the government of President Corazon Aquino but held out no hope for a further increase in the total amount of U.S. aid.

At a dinner attended by members of Aquino's Cabinet, Shultz also called on the fledgling government to return to popular elections and end rule by decree by November, as currently projected, as the key to attaining "long-term political stability" and "business confidence."

An anti-American demonstration by several hundred people at the airport shortly before Shultz's arrival and renewed Manila newspaper criticism of Reagan administration ties to deposed president Ferdinand Marcos symbolized the cooling of U.S.-Philippine relations since the turnover of power here 10 weeks ago.

Shultz's objective is to restore momentum to the relationship and to display the maximum U.S. support possible under the current U.S. budgetary cutbacks, according to officials with Shultz.

Shortly before leaving South Korea, where he conferred with President Chun Doo Hwan and declared that country to be far from the state of crisis that produced sudden change in Manila, Shultz said at a news conference that the Philippine economy is "a shambles" due to the problems left by Marcos.

Shultz was more positive in speaking to reporters as he flew toward his first visit to Manila since Aquino came to power in February.

While describing the problems as great, Shultz said he believed the flight of capital from the Philippines has stopped and a return of capital is "perhaps beginning."

In a gesture of support for the Aquino government, the U.S. administration recently asked Congress for $100 million in additional U.S. economic aid and $50 million in additional military aid.

Shultz said he believes disbursements of aid can be speeded to ease the cash problems of the Aquino government but said that congressional budget-cutting, which has already "gone much too far" in reducing U.S. international programs, made greater sums impossible.

"A strong, competent and apolitical military is essential to uphold a democratic system," said Shultz at the dinner attended by Defense Minister Juan Ponce Enrile and Armed Forces Chief of Staff Gen. Fidel Ramos, who played central roles in the ouster of Marcos.

In Seoul earlier in the day, Shultz ducked a press conference question about the proper political role of the South Korean military, which has dominated that government, often under martial law, for 25 years.

Reforms in the Philippine military under the new government "seem to be going ahead very impressively," Shultz said here.

He expressed limited enthusiasm for Aquino's effort to convince members of the homegrown Communist New People's Army to give up through political appeals, saying it is "quite understandable" to make such efforts.

Shultz said experience suggests that "in the end there is a hard core and you've got to fight with them." He added that this is a judgment for Aquino to make and that "as far as the United States is concerned, this is basically an internal problem."

It was not disclosed whether Shultz plans to renew President Reagan's recent request that the Aquino government issue a passport to Marcos to facilitate his departure from Hawaii, where he was given refuge by Reagan at the time of his overthrow.

The Aquino Cabinet yesterday debated and rejected the idea of providing a passport to Marcos.

Before leaving South Korea, Shultz met ruling party and opposition party leaders in a breakfast and held a business session and lunch meeting with Chun. Shultz did not meet Kim Dae Jung or Kim Young Sam, the most important opposition figures.

At a Seoul press conference, Shultz seemed to soften his criticism of the Korean opposition, saying he did not have the opposition party in mind when condemning "an opposition which seeks to incite violence" in earlier public remarks.

"It is not for the United States to take sides in the political debate of other countries," Shultz said when presented with the suggestion that his praise for Chun and barbs for the opposition seemed one-sided.

Lee Min Woo, the official head of the main opposition party, presented Shultz with his group's demand for restoration of direct presidential elections instead of election by an easily controllable group of 5,000 unpledged electors in the present system, adopted under martial law.

Shultz did not comment directly on the opposition demand but noted that the United States, through its electoral college, and Britain and Japan, through parliamentary systems, do not elect their leaders directly.