Japanese lawmakers scuffled Thursday as they tried -- and failed -- to stop the security bill that could see the military fight abroad for the first time in decades.

Opposition lawmakers climbed on top of one another as they tried to grab the committee chairman's microphone to prevent him calling a vote on the controversial bills.

In scenes uncommon for Japan's normally sedate parliament, the suited committee members lashed out at each other, pushing and shoving in a huge scrum in the second melee of the day.

But the mad-dash tactics, which came after hours of tortuous debate, failed to stop them from being approved as members of the ruling coalition stood up to signify their votes in favour.

The bills, which could see Japanese troops fighting abroad for the first time since World War II, are now expected to go to the full upper house later Thursday or Friday, where they will likely be passed to become law.

Some 500 protesters braved wet weather to gather outside parliament in plastic raincoats waving their umbrellas and shouting "stop the bills" as the committee debate rumbled on inside.

Some held up pictures of Prime Minister Shinzo Abe with a Hitler haircut and moustache.

Tens of thousands of people have taken to the streets to vent their anger during almost daily rallies over the past weeks, a show of public feeling on a scale rarely seen in Japan.

A total of 13 people were also reportedly arrested on Wednesday evening for "interfering with officers" during a rally that saw an estimated 13,000 people gather outside parliament in Tokyo.

The bills have taken a toll on Abe's once high popularity and opinion polls also show most voters oppose them.

Abe and his supporters say the bills are necessary to deal with a changing security environment marked by an increasingly assertive China and unpredictable North Korea.

Critics say the changes are unconstitutional and could drag Japan into American wars in far-flung parts of the globe.

- 'Are you listening?' -

Tensions were running high in parliament after the committee vote was repeatedly delayed through Wednesday night, as opposition lawmakers blocked doorways and packed the corridors of parliament in protest.

During the committee session, opposition lawmaker Tetsuro Fukuyama made an emotional speech outlining why his party had submitted a motion to delay the bills, which could see Japanese troops fight abroad for the first time since World War II.

"Is the ruling party listening to the voices of the public? You can do whatever you want to do because you have a majority -- is that what you think?" he said, on the verge of tears.

But Masahisa Sato, a senior ruling lawmaker who has promoted the bill, hit back after the bill was approved, saying: "This is legislation necessary to protect lives and happiness of Japanese people."

Opposition lawmakers were expected to propose a series of censure motions against Abe and his ministers at the plenary session, seen as a delaying tactic that would take hours to finish but will likely be voted down by the ruling bloc.

Under the planned changes, the military -- known as the Self-Defense Forces -- would have the option of going into battle to protect allies such as the United States even if there was no direct threat to Japan itself or its people.

Although the constitution, which bars troops from taking part in combat except in pure self-defence, was imposed by US occupiers, many Japanese feel strongly any change in the law would alter the country's pacifist character.

Abe is keen to get the bills passed before a three-day holiday next week.

The proposed legislation sailed through the lower house -- where Abe's coalition commands a two-thirds majority -- in July.