President Reagan has summoned congressional leaders to the White House this morning to hear the case for immediate additional military aid to El Salvador, administration officials said last night.

Secretary of Defense Caspar W. Weinberger, who estimated the additional aid requirement at $60 million, told the House Foreign Affairs Committee last Tuesday that the money is "a matter of survival" for the El Salvador government. He said the funds were needed for military supplies such as ammunition and helicopter spare parts.

Last year the administration asked Congress for $63.3 million in fiscal 1983 military aid for El Salvador. After the lawmakers failed to pass a foreign aid bill, only $26 million was available under a stopgap spending bill. Some of the money under discussion now would make up for this shortfall.

Weinberger indicated in his testimony that the administration probably would take $60 million in aid from a $75 million fund for "unforeseen emergencies," a procedure that would not require congressional approval.

However, a group of church and human rights organizations, the Coalition for a New Foreign and Military Policy, protested Thursday that this procedure would "purposely circumvent the authority of Congress."

As controversy built on Capitol Hill, administration officials said late last week that an emergency-fund allocation was only one of several options being considered. Others included a reallocation of funds from other programs, which would require the Appropriations committees' approval, and a special supplemental bill, requiring full congressional approval.

Regardless of which means is chosen, the request for more money is likely to rekindle congressional and public debate about El Salvador. It also presents a new necessity for the administration to discuss the military and political situation there at a time of increasing concern in Washington about the course of the conflict.

"The situation in El Salvador is deteriorating very rapidly," said Rep. Michael D. Barnes (D-Md.), chairman of the Latin American subcommittee of the House Foreign Affairs Committee. "If additional military assistance is to be provided, it should be with stringent conditions that policies be implemented to find a way out of this mess."

Barnes said there should be a search for a political solution. "Just pouring more money into the current policy doesn't make sense to me," he said.

Testifying before a House subcommittee last Wednesday, Secretary of State George P. Shultz continued to oppose proposals for negotiations between the Salvadoran government and guerrilla forces in search of a political settlement. Asked if United States would actively oppose such a move even if the Salvadoran government were to be interested, Shultz replied, "I wouldn't think it would be a good idea."