Japanese policemen contain protesters as they demonstrate against Japan's controversial national security bills in front of Japan's parliament building in Tokyo, Japan, Sept 14, 2015. [Photo/IC]

TOKYO - Crowds of protesters rallied on Wednesday as Japan's parliament moved close to passing bills for a defence policy change that could allow troops to fight abroad for the first time since World War II, despite opposition by many ordinary voters.

Demonstrators carrying banners that read "Scrap the unconstitutional war bills" lined the street near a hotel outside Tokyo where lawmakers were to hear public comments on the bills, which the government aims to get voted into law by parliament's upper house this week after committee approval.

It was the latest in a string of protests that, while smaller, echoed those which forced Prime Minister Shinzo Abe's grandfather, Nobusuke Kishi, to resign as premier after ramming a US-Japan security pact through parliament 55 years ago.

Abe's ruling bloc has an upper house majority, but major opposition parties have vowed to prevent a vote before parliament disperses on Sept 27 by using delaying tactics such as no-confidence and censure motions.

The bills have already been approved by the lower house.

The legal revisions include an end to a decades-old ban on defending a friendly nation under attack, or collective self-defence, when Japan faces a "threat to its survival".

The measures also expand the scope for logistics support for the militaries of the United States and other countries, and for participation in multinational peacekeeping operations.