Japanese Prime Minister Shinzo Abe looks set to put in motion this year his long-held goal of revising the country's war-renouncing Constitution, which was adopted 70 years ago today.

The leader of the ruling Liberal Democratic Party, which was founded in 1955 on the basis of making Japan a "normal country", said on Monday that Japan was primed for this "historic step", in conveying his hopes to table the changes in this milestone year.

Japan's resurgent right wing sees the pacifist Article 9, under which Japan forever renounces the right of war, as rendering it impotent in the face of looming security threats.

Any amendment would mark the first time that the Constitution, written by the United States after Japan's defeat in World War II, will be revised since its adoption in 1947.

Mr Abe told an annual bipartisan conference of politicians seeking constitutional reform that an "increasingly severe security environment" makes it timely to revise the supreme law of the land.

"The time is ripe. What we are seeking is a specific plan," he said. "We will definitely take a historic step during this milestone year towards the grand goal of revising the Constitution."

But he added that the changes will not be in the form of a 2012 draft proposal, which was deeply unpopular and deemed reminiscent of laws promulgated by the wartime government.

Said Mr Abe: "No matter how good the idea was, it will be fruitless without popular support."

While that draft proposal continued to stress pacifism, it reinstated the Emperor as "head of state" instead of merely a symbol, elevated the Self-Defence Forces to a full- fledged armed forces, and concentrated power in the Prime Minister in a state of emergency.

Mr Abe did not specify how he intends to revise the Constitution this time, but any such move requires the support of at least two-thirds of lawmakers in both Houses of the Diet - which the ruling coalition has - as well as a simple majority in a public referendum.

Despite recent public opinion polls to the contrary, Mr Abe said: "Those who think of the Constitution as an immortal code of laws to remain in effect forever are now a small minority."

A survey by Kyodo News showed 49 per cent of respondents in favour of revising Article 9, and 47 per cent against.

But in what observers say is indicative of the distrust of Mr Abe's motives, 51 per cent said they were against any constitutional amendments led by Mr Abe.

In a separate poll by public broadcaster NHK, 57 per cent opposed revising Article 9 while only 25 per cent approved of doing so.