Breaking with precedent, Prime Minister Shinzo Abe on Monday removed from his annual policy speech a paragraph outlining his vision for Japan's ties with South Korea, in a possible reflection of the neighbors' increasingly tumultuous relationship.

On the day that marked the opening of this year's 150-day regular Diet session, Abe delivered his seventh policy speech since his return to power in December 2012. In the speech Abe afforded South Korea only a passing reference, as he stressed the importance of "closely coordinating with the international community, in particular Washington and Seoul," to deal with nuclear-armed North Korea.

The speech — delivered each year at the start of the ordinary Diet session — was a departure from previous policy addresses that have seen Abe dedicate a whole paragraph detailing his desire to promote what he had often called "future-oriented" relations with Seoul.