Japan's ruling party said Wednesday the government should consider developing the capability to strike enemy bases if the country is attacked, citing North Korea's missile and nuclear threats.
For years Tokyo has harboured deep suspicion of Pyongyang and seen itself as increasingly vulnerable to its nuclear and missile ambitions.
North Korea conducted two nuclear tests last year and test-fired four ballistic missiles just this month, three of which landed off Japan's coast.
"North Korea's provocative acts are reaching levels our country can simply no longer overlook," a Liberal Democratic Party (LDP) security panel said in a proposal to be submitted to Prime Minister Shinzo Abe as early as Thursday.
The panel called on the government immediately to study ways to strike enemy bases if attacked, including through the deployment of cruise missiles.
It also urged the government to "immediately consider" if it should introduce the US Terminal High Altitude Area Defense (THAAD) and shore-based Aegis missile defence systems.
"We can't waste a moment to strengthen our ballistic missile defence," it said.
The recommendations, however, do not include calls for Japan to wield a so-called first strike capability, which would entail hitting an enemy before it could launch an attack.
Japan has maintained a strictly defence-only policy. Its pacifist constitution, imposed by occupying US forces after World War II, bans the use of force except in the strictest meaning of self-protection.
The United States stations some 47,000 troops in Japan and guarantees its security through a formal alliance.
Abe, who heads the LDP, is a staunch supporter of the security relationship with the US.
But he has long called for revising the constitution, seen by conservatives as an outdated legacy of the country's wartime defeat and occupation.
Under Abe Japan in 2015 passed a controversial new law that allows the Self-Defense Forces, the country's military, to go into battle to protect treaty ally the US.
Critics argue that doing so could drag Japan into distant foreign wars even if there was no direct threat to the country or its people, with some even saying the rules violate the constitution.
Abe and his supporters have argued the rules are necessary to deal with a changing security environment marked by an increasingly assertive China and an unpredictable North Korea.