Prime Minister Shinzo Abe is gaining political momentum to achieve one of his long-held goals as a key advisory panel prepares to propose that the government change its interpretation of the war-renouncing Constitution to let Japan engage in collective self-defense as defined by the United Nations.

Shunji Yanai, who heads the panel on security issues, said on an NHK program Sunday that the panel will propose the government change its interpretation by the end of this year.

"Current government views are so narrow and (Japan) has refrained from doing even what is not prohibited by the Constitution," Yanai argued. "In other words, use of collective self-defense has been accepted under international law and it is not prohibited by the Constitution."