The United States is sending about 1,300 additional military personnel to Panama to improve security for American bases as well as U.S. civilians living there, the Pentagon said Friday.

The move was being taken "in view of the growing unrest and tension" in Panama, and should not be read as an indication of "some kind of military action on the part of the United States," the Pentagon said.However, CBS News reported Friday night that the Reagan administration was "considering a plan to overthrow" Panamanian strong-man Manuel Antonio Noriega, although the network said no decision has been made and the Pentagon opposes such a proposal.

There are already more than 10,000 U.S. troops in Panama.

While many of the troops to be dispatched are military police and other security specialists, Army helicopter units also are being deployed to the troubled Central American country, the Pentagon said. The deployment will begin next week, the Pentagon said.

The move comes just one week after the Defense Department completed a buildup that had already doubled the number of security personnel guarding military bases in Panama. It also comes four days after Panamanian troops marched on a Panama City hotel, confiscating the tapes of four U.S. television networks and briefly detaining several American journalists.

CBS News reported Friday night that the Reagan administration was considering a proposal, advanced by the State Department earlier this week, "to overthrow Noriega by triggering a new political crisis" that would require the dispatching of two infantry brigades, or 8,000 combat troops, into Panama.

No decision has been made, the network said, noting that such a plan is opposed by Secretary of Defense Frank Carlucci and Adm. William Crowe, chairman of the Joint Chiefs of Staff.

Pentagon officials who demanded anonymity told The Associated Press late Friday that the decision to send the additional troops came after a lengthy and vociferous debate within the administration.

The sources confirmed that the State Department had urged the president to send an even larger contingent of troops to Panama, but that Carlucci had counseled greater caution.

The sources refused to say whether the State Department wanted extra troops in Panama to mount a military operation directly against Noriega, or rather thought there was more of a threat to Americans in the country.

State Department spokesman Rudy Boone said there was no comment on the CBS report. "We have nothing on that," he said.

The Pentagon denied any plans to send more troops into Panama. It described the upcoming troop movement as part of a continuing effort "to enhance our security posture there."

"The instability of the current situation in Panama, the heavy-handed tactics of Noriega in dealing with the situation and the potential for increased threats to U.S. citizens and interests in Panama make this deployment essential at this time to ensure the continued safety of U.S. personnel and facilities."

The Defense Department's prepared statement did not elaborate on who or what would be protected. But a ranking Pentagon official said the troops "will not be restricted to providing security at our bases."

"They will be able to go where they are needed to protect Americans," said the official, who requested anonymity.

"This action is consistent with the Panama Canal Treaty and is a reasonable and prudent effort to further safeguard the canal and U.S. lives, property and interests in the area," the Pentagon's statement said.

The Pentagon said the buildup would be gradual, with the first contingent of troops leaving the United States next Tuesday.