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HIGHLIGHTS-The Trump presidency on April 10 at 7:46 p.m. EDT/2346 GMT

April 10 (Reuters) - Highlights of the day for U.S. President Donald Trump's administration on Monday: SYRIA Trump is open to authorizing additional strikes on Syria if the use of chemical weapons continues there, the White House says.

The United States has made slight adjustments to its military activities in Syria to strengthen protection of American forces following its missile strikes last week on a Syrian air base that heightened tensions, U.S. officials tell Reuters.

The United States will hold responsible anyone who commits crimes against humanity, Secretary of State Rex Tillerson says, days after the unexpected attack on Syria.

Trump discusses the Syria strike in separate phone calls with British Prime Minister Theresa May and German Chancellor Angela Merkel.

RUSSIA The Kremlin says Tillerson will not meet President Vladimir Putin when he visits Moscow on Wednesday, a move that could point to tensions over the attack on Syria.

Tillerson's Moscow visit will be an early test of whether the Trump administration can use any momentum generated by the Syrian strike to craft and execute a strategy to end Syria's war.

SUPREME COURT Trump revels in the biggest political victory of his presidency at a White House ceremony in which his Supreme Court pick Neil Gorsuch is sworn in, poised to make an instant impact on a court once again dominated by conservatives.

NORTH KOREA China and South Korea agree to slap tougher sanctions on North Korea if it carries out nuclear or long-range missile tests, a senior official in Seoul says, as a U.S. Navy strike group heads to the region in a show of force.

BUSINESS LEADERS Trump will meet with about 20 chief executives on Tuesday including heads of General Motors , IBM, and Wal-Mart Stores as he works to gain support for a $1 trillion infrastructure program, tax reform and other administration priorities, a government official briefed on the matter says.

CLIMATE CHANGE The administration scuppers efforts by the Group of Seven industrialized countries to reach a common stance on energy when it asked for more time to work out its climate change policies.

BOKO HARAM Trump's administration is pushing forward with plans to sell up to a dozen aircraft to Nigeria's air force for the fight against the extremist group Boko Haram, a congressional source says, in a deal that could be worth up to $600 million.

(Compiled by Jonathan Oatis and Bill Trott; Editing by James Dalgleish and Lisa Shumaker)