SAN JUAN, Puerto Rico (AP) — The United Nations Security Council was evaluating options including the immediate activation of foreign troops to help free Haiti from the grip of gangs that has caused a scarcity of fuel, water and other basic supplies.

Such a force would “remove the threat posed by armed gangs and provide immediate protection to critical infrastructure and services,” as well as secure the “free movement of water, fuel, food and medical supplies from main ports and airports to communities and health care facilities,” according to a letter U.N. Secretary-General António Guterres submitted to the council on Sunday.

The letter, which was seen by The Associated Press and has not been made public, said one or several member states would deploy the force to help Haiti’s National Police.

It also states the secretary-general may deploy “additional U.N. capacities to support a ceasefire or humanitarian arrangements.”

However, the letter notes that “a return to a more robust United Nations engagement in the form of peacekeeping remains a last resort if no decisive action is urgently taken by the international community in line with the outlined options and national law enforcement capacity proves unable to reverse the deteriorating security situation.”

The letter was submitted after Haiti Prime Minister Ariel Henry and 18 high-ranking officials requested from international partners “the immediate deployment of a specialized armed force, in sufficient quantity,” to stop the “criminal actions” of armed gangs across the country.

The request comes nearly a month after one of Haiti’s most powerful gangs seized control of a key fuel terminal in the capital of Port-au-Prince, where some 10 million gallons of diesel and gasoline and more than 800,000 gallons of kerosene are stored.

Tens of thousands of demonstrators also have barricaded streets in Port-au-Prince and other major cities in recent weeks, preventing the flow of goods and traffic as part of an ongoing protest against a spike in the prices of gasoline, diesel and kerosene.

Gas stations and schools are closed, while banks and grocery stores are operating on a limited schedule.

Protesters are demanding the resignation of Henry, who announced in early September that his administration could no longer afford to subsidize fuel.

The deepening paralysis has caused supplies of fuel, water and other basic goods to dwindle amid a cholera outbreak that has killed several people and sickened dozens of others, with health officials warning that the situation could worsen.

On Sunday, Haitian senators signed a document demanding that Henry’s “de facto government” defer its request for deployment of foreign troops, saying it is illegal under local laws.

A spokesman for Henry could not be immediately reached for comment.

Haitian officials have not specified what kind of armed forces they’re seeking, with many local leaders rejecting the idea of U.N. peacekeepers, noting that they’ve been accused of sexual assault and of sparking a cholera epidemic that killed nearly 10,000 people during their a 13-year mission in Haiti that ended five years ago.

The letter that the U.N. secretary-general submitted Sunday suggests that the rapid action force be phased out as Haitian police regain control of infrastructure, and that two options could follow: member states establish an international police task force to help and advise local officers or create a special force to help tackle gangs “including through joint strike, isolation and containment operations across the country.”

The letter notes that if member states do not “step forward with bilateral support and financing,” the U.N. operation may be an alternative.

“However, as indicated, a return to U.N. peacekeeping was not the preferred option of the authorities,” it states.

The letter also says the Security Council could decide to strengthen the police component of the current United Nations Integrated Office in Haiti known as BINUH, and to call on member states to provide additional equipment and training to local police, which are understaffed and lack resources. Only about a third of some 13,000 are operational in a country of more than 11 million people.

The secretary-general said the issue is a matter of urgency, noting Haiti “is facing an outbreak of cholera amid a dramatic deterioration in security that has paralyzed the country.”

The U.S. Embassy has granted temporarily leave to personnel and urged U.S. citizens to immediately leave Haiti.