MANILA — President-elect Rodrigo Duterte said Monday he will reimpose the death penalty, offer Cabinet posts to communist rebels, and move to amend the Constitution to give more power to the provinces, in some of his first policy pronouncements since winning last week’s election based on an unofficial count.

In his first nationally televised news conference since the May 9 vote, Duterte also said he will launch a major military offensive to destroy Abu Sayyaf extremists on southern Jolo Island.

The announcements, a sharp departure from current government policy, reflect his brash campaign pledge to end crime and corruption in the impoverished nation in three to six months.

Police officials have said the plan is undoable, and that crime remains prevalent in Davao city, where Duterte has served as mayor for more than 22 years.

The military has been fighting a decades-long Marxist insurgency in the countryside.

Duterte said he would probably offer the Cabinet posts of environment and natural resources, agrarian reform, social welfare, and labor to the communist rebels. ‘‘They are the most vigilant group in the Philippines about labor so they would get it,’’ Duterte said.

The move would likely be strongly opposed by big business and industry.

Duterte said he would ask Congress to reimpose the death penalty, which has been suspended since 2006 in the face of staunch opposition from the dominant Roman Catholic church. Capital punishment by hanging, he said, should be imposed for heinous crimes, and criminals convicted of killing along with robbery and rape should be meted ‘‘double the hanging.’’

‘‘After the first hanging, there will be another ceremony for the second time until the head is completely severed from the body,’’ he said.

Commission on Human Rights chairman Chito Gascon said his agency opposes the death penalty and would block any attempt to reimpose it, adding that the Constitution forbids cruel and degrading punishments like hanging.

‘‘In a country where the rule of law has so many loopholes and problems, what will happen is the possibility of a mistaken conviction,’’ Gascon said.

Duterte also plans to switch to a federal form of government, aiming to give more power and resources to regions, including the country’s south, where Davao city is located. Such a change would require an constitutional amendment.

In a populist move, Duterte said he would sell the presidential yacht and use the money to buy medical equipment for military and police personnel.

‘‘When people are hungry and jobless . . . it would be an obscene thing’’ to have the luxury vessel lying unused, he said.

TV network ABS-CBN also quoted him as telling reporters in Davao late Sunday that he plans to ban the use of luxury cars by Cabinet members and will use his personal pickup truck as his official presidential vehicle.

Duterte reiterated Monday his vow to control illegal drugs and crime, even if it means losing the presidency or his life. ‘‘Stop messing with me, because I have a sacred promise to save the next generation from the evil of drugs,’’ he told critics.