Japanese and Philippine leaders head to Washington this week for a trilateral summit aimed at boosting defence ties, hot on the heels of four-way military drills in the South China Sea with Australia.

A major upgrade of US defence ties with increasingly self-confident Japan could be announced, as well as joint coast guard patrols with Manila in areas disputed with China.

Also on the agenda will be securing access to vital supplies such as semiconductors and rare metals, North Korea's growing belligerence, and the Japanese takeover of US Steel opposed by President Joe Biden.

The talks will "advance a trilateral partnership built on deep historical ties of friendship, robust and growing economic relations... and a shared vision for a free and open Indo-Pacific," the White House said.

- Full honours -

The summit kicks off Wednesday with Fumio Kishida becoming Japan's first prime minister since Shinzo Abe in 2015 to be received with full honours at the White House.

This will include a gala dinner for him and his wife Yuko Kishida hosted by Biden and First Lady Jill Biden. Biden and Kishida will also hold a joint news conference in the Rose Garden.

On Thursday, Kishida, 66, will address both houses of Congress before he and Philippine President Ferdinand Marcos convene with Biden for the countries' first trilateral summit.

Biden, 81, and Marcos, 66, who is seen as closer to Washington than his more China-leaning predecessor Rodrigo Duterte, will also hold separate talks.

They are the latest Asia-Pacific allies to be hosted by Biden, who was joined by Kishida and South Korean President Yoon Suk Yeol at Camp David in August.

Biden has also moved to manage tensions with China, holding a two-hour phone call with President Xi Jinping last week and a face-to-face meeting in San Francisco in November.

- 'Momentous changes' -

Staunchly pacifist for decades, Japan has in recent years made "some of the most significant, momentous changes" since World War II, US ambassador to Japan Rahm Emanuel said ahead of the visit.

This includes plans to double military spending, buying US Tomahawk missiles, easing rules on exporting weapons and creating a joint operations command for its Self-Defense Forces (SDF).

It is also providing funding, equipment and patrol vessels to countries across the region and is in talks with the Philippines about allowing troop deployments on each other's soil.

Manila has a similar agreement with Australia and the United States.

According to media reports, Biden and Kishida could agree to the biggest upgrade in US-Japan command and control structures in decades.

This would make their two militaries more nimble in a crisis, for example a Chinese invasion of Taiwan, experts said.

"Currently, despite their close inter-operability, US forces in Japan and SDF operate under separate commands," said Yee Kuang Heng from the University of Tokyo's Graduate School of Public Policy.

The US has 54,000 military personnel in Japan who must report back to Indo-Pacific Command in Hawaii, around 6,500 kilometres (4,000 miles) away and 19 hours behind, for joint operation matters.

"This is seen as not fit for 21st century purposes given the severe security environment around Japan," Heng told AFP.

The two countries may also agree to large US warships being able to undergo repairs at private shipyards in Japan, and to joint production of defence equipment, media reported.

- Joint drills -

China claims territorial sovereignty over nearly all of the South China Sea and has been increasingly aggressive in the region in recent years.

On Sunday, the US, Japanese, Filipino and Australian militaries conducted joint exercises to "(ensure) that all countries are free to fly, sail, and operate wherever international law allows," US Defense Secretary Lloyd Austin said in a joint statement.

China's People's Liberation Army (PLA) Southern Theater Command said it was organising "joint naval and air combat patrols in the South China Sea" the same day.

- Trump round two -

Marring the mood music between Washington and Tokyo at the summit is Biden's opposition to Nippon Steel's proposed $14-billion acquisition of US Steel, based in Pennsylvania, a key election battleground state.

Looming over the talks is also the prospect of Donald Trump returning to the White House after US elections in November and the potential disruption that the 77-year-old could bring to US allies.

"I would not be surprised if Japanese officials and businesses were reaching out to people close to former President Trump," Naoko Aoki, political scientist at Rand Corporation, told AFP.

"I am sure the US election is very much on their minds."