The president rolled out the red carpet and pageantry for the royal couple’s state visit, the first of Trump’s second term.
The justices, who have yet to issue a final decision, declined to overturn a lower court ruling that the referendum process violated the state constitution.
The king’s roughly 35-minute speech comes as the United States prepares to celebrate its 250th anniversary in July.

The recall impacts 4,750 prescription-only bottles of pantoprazole sodium, a notice said.
One major survey indicated slightly more optimism while another gauge fell to its lowest level in decades.
On April 23, the Trump administration said it was moving forward with the reclassification of approved marijuana, following last year’s executive order.
The projects’ owners agree not to invest in any new U.S. offshore wind projects in the future.
Christopher Yeaw, U.S. assistant secretary of state for arms control and nonproliferation, said the decision was ‘beyond shameful.’

Supreme Court heard arguments as demonstrators warned Monsanto ruling could erase thousands of pending cancer claims.
A legal challenge to the state’s redistricting amendment was argued Monday before its Supreme Court.
Prosecutors alleged that Xu Zewei was responsible for initial breaches of Microsoft Exchange servers that targeted thousands of computers worldwide.
The board oversees the National Science Foundation.
The ruling means the new map that favors Republicans will remain in place for the November congressional elections.
The possibility of a U.S. exit from NATO leaves European leaders assessing military capabilities without American might.
A bitter feud between the tech billionaires stems from allegations that Altman betrayed the company’s nonprofit mission.
Last year, more than 191,000 complaints related to phishing or spoofing scams were reported to the FBI’s Internet Crime Complaint Center.
The president later confirmed that one Secret Service agent had been shot during the incident, but is ‘doing great.’
The amendment would also direct the secretary of state and county registrars to keep accurate voter rolls and verify citizenship.
The last time the United States deployed three aircraft carriers to the region was in 2003.