The Carter administration has begun supplying arms to Tunisia in an effort to help President Habib Bourguiba's moderate government respond to pressures from neighboring Libya, U.S. officials disclosed yesterday.

The decision to give Tunisia 30 armed personnel carriers and six military helicopters marks the first time the United States has supplied heavy arms to the North African country.

Ten armored personnel carriers have already been airlifted to Tunis following an urgent Tunisian request for arms in the wake of a Libyan-inspired revolt in southern Tunisia last month, officials said. The remaining equipment will be sent by sea.

Yesterday's disclosure coincided with President Carter's statement that he views with "deep concern" any foreign threat against the pro-Western government in Tunis.

Carter, speaking after he received a personal message from Bourguiba delivered by the Tunisian leader's son, noted that the two countries have maintained close and friendly relations ever since Tunisia became independent in 1956.

"We have observed with deep concern any threat to the independence and freedom of the people of your country," Carter told Habib Bourguiba Jr. The president commended Tunisia's support "given us in times of crisis and common challenge."

The Tunisian arms package comes in the wake of increased U.S. arms supplies to Morocco, another North African country with close ties to the United States.

The Tunis package totals about $23 million. It involves the light transport helicopter UH-IN and the standard armored personnel carrier, both designed to give greater mobility to the Tunisian armed forces along its long border with Libya. The arms are supplied under U.S. foreign military credit sales.

It also disclosed that France was supplying six transport aircraft to Tunisia while Italy was prepared to provide an unspecifed number of helicopters.

The recent decision to strengthen Morocco's armed forces against Polisario insurgents in Western Sahara involved six F5E aircraft, 8 helicopter gunships and six OV10 Bronco aircraft.

Bourguiba made an appeal for help last month when his military forces repelled an attack on the town of Gafsa, in southern Tunisia, by anti-Bourguiba rebels. Tunisia has claimed that the radical regime of Libyan leader Muammar Quaddafi had instigated the attack in which 41 persons were killed and 111 wounded.

Apart from its longstanding feud with Libya, the Bourguiba government has come under increasing fire lately from other radical Arab states because of its generally moderate, pro-Western positions. Along with Egypt, Tunisia has been the most outspoken Arab country in supporting Washington over the Iranian hostage situation.

The increase in U.S. arms supplies has both symbolic and practical value for Tunisia. In the past, the United States has sold only modest quantities of light military equipment to Tunisia.

The U.S. decision symbolizes Washington's political backing for the moderate government in Tunis which has been subjected to increasingly virulent propaganda assaults from Libya. It will also help strengthen the Tunisian Army, which was reportedly taken by surprise during the Gafsa incident.