In the run-up to a planned historic summit between the U.S. and North Korean leaders, Japan has won broader international backing for its efforts to address past abductions of its citizens by North Korea and the security threat from the country.

Following U.S. President Donald Trump's promise to do "everything possible" to repatriate Japanese abductees snatched in the 1970s and 1980s, the Group of Seven industrialized nations affirmed close coordination in resolving the issue as well as in ridding Pyongyang of nuclear weapons and removing all North Korean missiles including shorter-range missiles capable of hitting Japan.

"I have won support from my G-7 counterparts for the immediate resolution of the abduction issue," Japanese Foreign Minister Taro Kono told reporters during a two-day meeting that ended Monday in Toronto with counterparts from Britain, Canada, France, Germany, Italy, the United States plus the European Union.

Dispelling concerns that Japan has been left behind in a flurry of diplomacy over North Korea, Trump assured Prime Minister Shinzo Abe last week that he will push Kim Jong Un "very hard" to bring Japanese abductees back home and that he will be "very loyal" to Washington's alliance with Tokyo.

"We're going to do everything possible to bring them back to Japan. I gave you that promise," Trump said at a joint news conference with Abe after their April 17-18 talks in Florida. "We will be very loyal to Japan."

Earlier, there had been worries that Trump might strike a deal with Kim to lift sanctions in return for North Korea suspending test-launches of intercontinental ballistic missiles targeting the United States.

Such a deal, if struck, would be tantamount to U.S. acceptance of Japanese and South Korean vulnerability to the North's short- and medium-range ballistic missiles, a development that would significantly undermine the U.S. alliances with the two countries.

U.S. Acting Secretary of State John Sullivan underscored Trump's assurances during a meeting Monday with Kono in Toronto.

Sullivan and Kono "affirmed their strong determination to bolster the U.S.-Japan alliance and maintain international unity for diplomatic and economic pressure on North Korea until it denuclearizes," the State Department said.

(Taro Kono, left, has the backing of his counterparts on abduction issue)

In what may be an attempt by Pyongyang to decouple Japanese abductees and three Americans being detained in North Korea, Kim, in a recent meeting with Central Intelligence Agency Director Mike Pompeo in Pyongyang, gave assurances that a summit with Trump could be paired with the release of three detained Americans, the Wall Street Journal reported Friday, citing people briefed on the Kim-Pompeo meeting.

The issue of detained U.S. citizens is particularly sensitive to the Trump administration following Pyongyang's release last year of Otto Warmbier, a University of Virginia student who returned home in a coma and died shortly afterward.

However, U.S. Ambassador to Japan William Hagerty said a Trump-Kim meeting would address the Japanese abductees as well as the three American detainees, alongside the complete, verifiable and irreversible denuclearization of North Korea, its other weapons of mass destruction -- chemical and biological -- and its ballistic missile programs.

Japan officially lists 17 citizens as abduction victims and suspects North Korea's involvement in many more disappearances. While five of the 17 were repatriated in 2002, Pyongyang maintains that eight have died and the other four never entered the country.

Trump will not meet with Kim as planned "if he feels that this meeting is not going to be productive and it's not going to advance U.S., Japan and international interests," Hagerty told journalists after the Abe-Trump talks.

Experts on Japan-U.S. relations welcome Trump' commitment to the alliance with Japan as he prepares for what will be the first-ever U.S.-North Korea summit, but point out that the United States must step up coordination with Japan and South Korea, as well as partners like China, as the process toward the permanent denuclearization of the Korean Peninsula evolves.

"It was largely a strong reassurance statement to Japan: 'Not to worry, I won't forget your interests, I have the abductees at heart, I have your security at heart, the alliance will do nothing to compromise Japanese interests,'" said Sheila Smith, senior fellow for Japan studies at the Council on Foreign Relations, a U.S. think tank.

"I think you can walk away fairly reassured with (Abe's) taking him at face value," Smith said but noted that "in the long run, it may be a question of just when and how Japanese interests balance with the interests of the South Koreans and the interests of the U.S. government."