TOKYO (Kyodo) -- Japan's opposition camp was critical Tuesday of Japan-U.S. tariff negotiations after Prime Minister Shigeru Ishiba and President Donald Trump failed to reach a deal at their summit in Canada, while ruling party members struck a more positive note.

A senior member of the largest opposition Constitutional Democratic Party of Japan said the meeting on Monday had been "terrible," while Yuichiro Tamaki, head of the small opposition Democratic Party for the People, said he felt it "showed almost no progress and no substantive content."

Ishiba had said his talks with Trump on the sidelines of the Group of Seven leaders' summit in Kananaskis would be a "milestone" in efforts to get the United States to rethink its tariff policy. But they concluded with him saying that bilateral ministerial negotiations would continue in pursuit of a mutually beneficial agreement.

As the meeting came before the U.S. president left the G7 summit a day early amid the unfolding Israel-Iran conflict, the CDPJ official added that "for Mr. Trump, it might not have been the right time for tariff negotiations."

The Trump administration has slapped on longtime U.S. ally Japan what it calls "reciprocal" tariffs, as well as additional levies on the auto sector and steel and aluminum, raising concerns for Japan's export-driven economy.

The tone was more positive in the ruling camp, with Hiroshi Moriyama, secretary general of the Liberal Democratic Party, saying he intends to "continue to offer support and watch developments in the Japan-U.S. tariff talks," and that the leaders had "a candid exchange of views."

Chief Cabinet Secretary Yoshimasa Hayashi, the government's top spokesperson, said the two sides were "deepening their mutual understanding."

He added that intensive coordination toward a mutually beneficial agreement will continue "while firmly protecting our national interests."