Shinzo Abe has become Japan's longest-serving prime minister after breaking a record set more than a century ago.

Abe's total tenure reached 2,887 days on Wednesday. Abe first became prime minister in 2006 but resigned a year later over health issues. Since returning to the top post in December 2012, he has worked to revive the economy, promote work-style reforms and provide childcare support.

Abe promotes what he calls "foreign policy that takes a panoramic perspective of the world map."

But his long period in office has drawn criticism. Several allegations of favoritism arose, including a state land sell-off scandal.

The Finance Ministry sold land to a school operator at a price that was millions of dollars below the market value. Abe's wife, Akie, was slated to become honorary principal of the school planned for the site, sparking criticism. Ministry officials were later found to have altered official documents for the sale.

Opposition lawmakers have accused Abe of using taxpayers' money to entertain his constituents by inviting hundreds of them to a publicly-funded cherry blossom-viewing party.

There's no term limit for a prime minister in Japan. But Abe's third and final term as president of the governing Liberal Democratic Party will end in September 2021, setting an effective limit on his premiership. By then, he is likely to pursue his long-held wish of amending the Constitution.

Attention is also focused on whether Abe can make progress in resolving North Korea's abductions of Japanese citizens as well as Pyongyang's nuclear and missile development.

Another key issue is negotiations with Russia for a peace treaty that would include a resolution of a long-standing territorial issue over four Russian-controlled islands.

The Japanese government maintains they are an inherent part of Japan's territory. It says the islands were illegally occupied after World War Two.