President Corazon Aquino signed a land reform bill Friday and said she hoped the measure would uplift millions of rural Filipinos from their ancient poverty.

She congratulated Congress for enacting the legislation after nearly a year of debate and said the measure would contribute to the true independence of the Filipino people.The bill, approved by Congress last Wednesday, gives landowners the choice of dividing their property among tenants or sharing profits with them.

It is expected to benefit two million landless farmers in this largely agricultural nation of 7,100 islands. Land reform is considered essential to defeating the 19-year Communist insurgency, which draws its support primarily from rural areas.

"Few measures have been as rigorously scrutinized and discussed as this program has been by representatives of the people and by the people themselves," Mrs. Aquino told a national televisaudience after signing the measure.

"I should hope that now the various interests in the land will be able to work together to achieve the twin goals of the program, a radical leap in agricultural productivity and, therefore, a significant contribution by the agricultural sector to Philippine progress and the upliftment of the Filipino masses from their ancient poverty."

Under the plan, each landowner may retain 12 acres and an additional seven acres for each direct heir over age 15 who will till the land. A landowner has the option of sharing profits or giving workers shares of stock instead of physically dividing the property.

"Let us see the program not as a taking of property from some and a giving of it to others, but rather as a way of liberating the hitherto suppressed energies and creativity of the nation for the material upliftment of the many and prosperity of all," she added.

Leftist farm groups have branded the plan a "grand deception" because they claim it does not go far enough in breaking up huge estates and redistributing property to the landless.

Rep. Bonifacio Gillego, who sponsored the bill in the House but voted against the measure after amendments, claimed the law would bring about agrarian reform "through a revolution."

He predicted Communist rebels would seek to undermine the program by trying to convince rural Filipinos that it was a sham.

Other critics said the success of the plan will depend on the government's success in providing credits, expertise and other support to new landowners.

"The main responsibility for the implementation of the program lies with the Department of Agrarian Reform," Mrs. Aquino said. "But I expect all the other departments, the entire apparatus of government, civil and military, to be as deeply involved and as committed to its success.

The law also provides for the distribution to farm workers of tracts of public land greater than 2,470 acres now leased to multinational corporations.

Government lands will be the first distributed in the 10-year program. Private holdings of more than 123.5 acres will be parcelled out in the first four years and smaller holdings later.

Owners of more than 123.5 acres will be paid 25 percent of the value in cash and those with less than 60 acres will be paid 35 percent in cash. Tax exemptions, shares of stock in government-run corporations or Land Bank of the Philippines bonds will make up the rest of the compensation.

Officials say the program, estimated to cost $70 billion, will be financed by foreign aid and assets of exiled former President Ferdinand Marcos and his associates that were seized on grounds they were illegally acquired.

Marcos ruled the Philippines for 20 years and was driven from the country by a civilian-backed military uprising that swept Mrs. Aquino to power in February 1986.

The Philippines attempted about a dozen land reform programs in the past, but they failed either for lack of funds or resistance from landowners.

Land reform was among the demands of pro-Soviet Huk rebels in the 1950s and early 1960s and is a major demand of communist rebels in the current insurgency, which began in 1968.