TOKYO (Reuters) - Japanese Prime Minister Shinzo Abe said on Wednesday he hoped the first-ever change to the country’s 70-year-old pacifist constitution would be enacted by 2020, and that it would enshrine the status of the military.

Japan's Prime Minister Shinzo Abe speaks during a news conference at a hotel in London, Britain April 29, 2017. REUTERS/Peter Nicholls

Under the constitution’s Article Nine, Japan forever renounced its right to wage war and banned maintenance of a military, though successive governments have interpreted it to allow a military exclusively for self-defense.

Japanese troops have taken part in international peace-keeping operations, as well as a non-combat reconstruction mission in Iraq from 2004 to 2006.

Abe, in a video message to a gathering celebrating the anniversary of the enactment of the charter, proposed making explicit reference to the Self-Defense Forces (SDF) in the constitution. The document currently does not make any mention of the force.

“By making explicit the status of the SDF in the constitution, we should leave no room for contending that the SDF may be unconstitutional,” he said in the video, aired by Japanese television broadcasters.

“I strongly hope to make 2020 the year in which a new constitution takes effect,” Abe added.

It was his first public mention of a date. A recent ruling Liberal Democratic Party (LDP) rule change means Abe could well still be prime minister in 2020 if his party stays in power.

Under Abe’s watch, parliament in 2015 voted into law a defense policy shift that could let troops fight overseas for the first time since 1945, but any formal constitutional revision would require the backing of two-thirds of members of both houses of parliament and a majority of voters in a referendum.

But voters are divided over his campaign to revise the constitution, against a backdrop of growing tension in the region, particularly over North Korea, according to a poll released on Wednesday.

A Nikkei Inc/TV Tokyo survey showed support growing for Abe’s push to revise a charter written by the United States after Japan’s defeat in World War Two and never amended.

About 46 percent of respondents favored keeping the constitution as it is, four percentage points lower than a similar poll last year.

The number favoring a change stood at 45 percent, up five percentage points from a year ago.

Nuclear-armed North Korea has over the past year stepped up missile tests, the most recent of which was a failed launch on Saturday.

It has also threatened to attack Japan.

In March, Abe’s LDP formally proposed that the government consider acquiring the capability to strike enemy bases and beef up missile defense in the face of the North Korean threat.

Acquiring such weapons would likely anger China, where bitter memories of Japan’s wartime aggression run deep.

A separate survey released by Kyodo News on Saturday showed 49 percent of respondents said Article Nine needed to be revised, against 47 percent opposing a change.