Starting his second day in Asia under under the cloud of another mass shooting in the United States, President Trump told business leaders in Japan that too many trade deals have benefited foreign partners at the expense of Americans.

"I have to say for the last many decades Japan has been winning — you do know that," Trump told Japanese and American business leaders meeting Monday morning in Tokyo, Sunday night in the United States.

Trump began his speech by citing more tragedy in the U.S., and pledging the federal government's help to the victims of Sunday's mass shooting at a church in Texas.

"All of America is praying to God to help the wounded and the families of the victims," Trump said in Tokyo. "We will never ever leave their side — ever."

Trump later issued a proclamation honoring the victims of "this unprovoked act of violence," and ordered U.S. flags at public buildings to be flown at half-staff until sunset on Thursday.

Trade is a major theme of the Trump trip to Asia that will also take him to meetings with leaders in South Korea and China, as well as economic conferences in Vietnam and the Philippines. The president also is using the trip to campaign against North Korea's nuclear weapons program.

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Trump has threatened to seek changes to various U.S. free trade deals, including one with South Korea; officials in other countries have said that Trump is exaggerating the shortcomings of free trade and underestimating the benefits to the United States.

Japan, in particular, criticized Trump for pulling the United States from the proposed Trans-Pacific Partnership, a massive agreement among Pacific Rim nations designed to increase economic activity and lower prices for all members.

In his meeting with Japanese and American business leaders, Trump said too many free trade deals have helped U.S. businesses move overseas, leaving behind newly unemployed Americans. He also complained about U.S. trade deficits — almost $70 billion annually with Japan — and said other countries need to open their markets to more American products like cars.

"We want free and reciprocal trade, but right now our trade with Japan is not free and it's not reciprocal," Trump said. "And I know it will be."

Trade was a major topic of Trump meetings Monday with Japanese leader Shinzo Abe. While the two leaders have gotten along in public, including while playing a round of golf on Sunday, they have different views of the trade issue.

Trump and Abe will conduct a joint news conference on a day devoted largely to symbolic events.

After his remarks to the business leaders, the president and first lady Melania Trump visited with Emperor Akihito and Empress Michiko of Japan at the Imperial Residence. Earlier in the day, the Trumps greeted employees at the U.S. embassy in Tokyo.

Prime Minister Abe later staged a formal welcoming ceremony for the Trumps at the government palace, where the two leaders reviewed troops, had a "working lunch," and held a bilateral meeting.

In public remarks, Abe called the U.S.-Japanese alliance "the foundation for peace and prosperity in the Asia Pacific region." The Japanese leaders also expressed "my heartfelt condolences and sympathy for your loss and also for those who lost their lives and those who were hurt" in the mass shooting in Sutherland Springs, Texas.

Trump thanked Abe for his hospitality, and said he looked forward to talks about trade and mutual security.

"We will continue to have a relationship that's even better than we have ever had with Japan," Trump said.

Another event in Tokyo underscored a second major theme of Trump's Asia trip: confronting North Korea over its nuclear weapons. Trump is urging Asian nations to put economic pressure on Kim Jong Un's government, trying to force it to give up nuclear weapons.

In Tokyo, Trump planned to address Kim's aggression in a meeting with families of Japanese citizens who have been abducted by North Koreans.

On Monday evening, Abe will host a state banquet for Trump.

Follow David Jackson on Twitter: @djusatoday