PANAMA CITY, Panama--Panamanian strongman Gen. Manuel Antonio Noriega, under indictment in the United States on drug trafficking charges, was ordered by the president yesterday to step down as military chief.

President Eric Arturo Delvalle also named Panama's current chief of staff to replace Noriega, who is regarded as the real power behind the civilian government of Panama.

"There is no other alternative but the use of the powers that the constitution gives me, to separate Gen. Noriega from his high command," Delvalle said yesterday.

But it was unclear yesterday whether Noriega, who has denied U.S. accusations against him, would comply with Delvalle's order.

The announcement comes amidst rapidly souring relations between the U.S. and Panama over Noriega's alleged assistance to Colombian drug merchants that was revealed in recent Congressional testimony.

Devalle's announcement was met with some opposition yesterday as members of the military vowed their support for Noriega.

The police chief for the Defense Forces, flanked by colonels and lieutenant colonels, told Panamanian TV that neither Col. Marcos Justine, the man named to succeed Noreiga, nor any other officer would replace Noriega.

"He is going first," Col. Leonidas Macias said, referring to Delvalle.

Col. Elias Castillo, chief of defense land transportation, said, "All the chiefs of staff, all the middle commands, officers and classes and troops, support our Gen. Manuel Antonio Noriega. He is the only commander of the Defense Forces."

The military officers were grouped at the central garrison of the Defense Forces, a short distance from the former Panama Canal Zone.

White House spokesman Marlin Fitzwater issued a statement in Washington saying, "We understand that President Delvalle today dismissed Gen. Noriega from his position as commander of the Panama Defense Forces."

"At this time, we want to reiterate our unqualified support for civilian constitutional rule in Panama. There is but one legitimate sovereign authority in Panama and that is the Panamanian people exercising their democratic right to vote and elect their leadership in a free society."

Washington called for Noriega to resign after U.S. grand juries in Miami and Tampa, Fla., indicted him and others on drug trafficking charges on Feb. 5.

The U.S. indictments accuse Noriega of allowing Colombian drug traffickers to use Panama as a base for smuggling cocaine and marijuana into the United States. The charges said Noriega received a healthy kickback from drug profits. His take was put at up to $4.8 million.

Pentagon spokeswoman Capt. Nancy LaLuntas said in Washington that the U.S. Southern Command in Panama received reports of scattered demonstrations in and around Panama City. U.S. forces were put on "Bravo" alert, which orders American military personnel and dependents to "decrease their visibility," she said.

The command, initially created to protect the Panama Canal, has become the center for U.S. military operations in Latin America which range from fighting rebels to fighting drug smugglers. There are 10,000 soldiers and 2000 U.S. dependents under the command.

Delvalle said in a nationally broadcast message that he asked Noriega days ago to step down voluntarily so an investigation could begin of charges that he engaged in illicit activities. He said Noriega refused.

Some drivers sounded the horns of their vehicles shortly after Delvalle made his announcement, and some groups could be seen waving white handkerchiefs. Both are signs of protest used by Noriega's opponents.

But an hour after the speech, the capital's streets were nearly deserted.

Panama has been rocked by protests since last June, when Noriega's recently retired second in command publicly charged the general with illicit activities ranging from drug trafficking to electoral fraud and the assassination of a political opponent.