The Cabinet on Tuesday approved guidelines on the handling of state secrets before a controversial secrecy law that toughens penalties for leakers takes effect on Dec. 10 — leaving unaddressed concerns that the public’s right to know will be undermined for the sake of national security.

Under the guidelines, state secrets are defined in 55 categories, such as information about the development and capabilities of submarines, aircraft, weapons and ammunition.

Intelligence and images obtained via radio waves and satellites and provided by foreign governments and international organizations could be withheld from the public.

The guidelines state that the government will “designate the minimum amount of information as secrets for the shortest period of time possible,” and that the public’s right to know should be “greatly respected as it is linked to the existence of a democratic society” and freedom of expression.

Chief Cabinet Secretary Yoshihide Suga said the guidelines will create “a mechanism to ensure the law will be applied appropriately,” telling reporters that the government will try to dispel public concerns that information can be withheld at its own discretion.

Under the secrecy law that cleared the Diet last December, the heads of 19 ministries and agencies can designate as special secrets information deemed sensitive in the areas of diplomacy, defense, counterterrorism and counterespionage.

Leakers, including civil servants, could face up to 10 years in prison and those who instigate leaks, including journalists, will be subject to five-year prison terms. The initial five-year designation period can be extended for up to 30 years.

If approved by the Cabinet, designated state secrets can stay classified for up to 60 years.

The government will set up hotlines so whistle-blowers such as civil servants who are authorized to handle state secrets can report when they have suspicions about arbitrary classification or declassification of state secrets in violation of the law or the guidelines.

Still, whistle-blowers will be obliged not to reveal details of the state secrets they are dealing with in reporting suspicious handlings, the guidelines say.

The guidelines are subject to revision five years after the law takes effect Dec. 10.

Criticism has been directed at the absence of an independent watchdog mechanism, as new oversight entities will be placed under government control. The prime minister will be required to report to the Diet annually on the designation, safeguarding and disclosure of state secrets.

Opposition lawmakers and critics have argued that the law will limit public access to information, saying the definition of “specially designated secrets” is too vague and leaves room for interpretation.

Abe has said the law is necessary for Japan to exchange sensitive information with other countries and forge closer security ties. The government set up its National Security Council last December to speed up decision-making on diplomacy and defense.

An advisory panel on information protection gave its nod in September to the guidelines, which were crafted and revised by the government amid a flurry of public criticism during a monthlong review period.

The Liberal Democratic Party put off its approval of the guidelines Oct. 7, saying more discussion was needed, but gave the green light three days later.

Some 20 protesters gathered outside the prime minister’s office on Tuesday, demanding the government scrap the law.

“Setting the law to take effect on Dec. 10, which is the U.N.-designated Human Rights Day, is a challenge to the world and must not be tolerated,” said Koji Sugihara, leader of the citizens’ group that held the rally. “We should postpone the law’s enforcement, and have it drastically reviewed.”