WASHINGTON -- President Donald Trump is continuing to check off his campaign promises in his first week in office.
He's also showing he's not beholden to previous agreements.
Trump travels to Philadelphia Thursday to generate brotherly love among Republicans in Congress.
He's there for a strategy session designed to put GOP lawmakers on the same page on issues like replacing Obamacare during these crucial early days of his administration.
The president is moving ahead with his agenda through executive actions.
He's expected to put a temporary halt on the flow of refugees into the U.S. and direct his administration to stop issuing visas for people from countries with strong ties to terrorism, including Iran, Syria and Yemen.
After signing an executive order to begin the process of building a wall along the nation's southern border, Trump renewed his promise that Mexico will pay for the construction.
"We're going to be starting those negotiations relatively soon and we will be in a form reimbursed by Mexico," Trump promised.
But Mexican President Peña Nieto said Mexico will not be paying for the wall.
"I regret and reject the decision of the U.S. to build the wall," said Nieto.
He is scheduled to meet with Trump next week but is considering canceling his trip following the president's order to build the wall.
Happy Day on Wall Street
The president's executive actions on trade, manufacturing and business deregulation are driving optimism on Wall Street. The Dow Jones industrial average crossed the 20,000 milestone this week.
"Donald Trump joined in on the celebrations of yesterday's 20,000 marker and to a large degree he is to thank for it coming to fruition," said Joshua Mahony, market analyst at IG.
"Despite the divisive nature of Trump's policies, markets have come to the realization that money talks," he added. "And with many of his other policies coming to fruition, it seems a fiscal spending package is just around the corner."
And the president is launching an investigation into voter fraud.
"I think in terms of registration where you have people on rolls who are deceased or moved or are registered in two counties," explained White House press secretary Sean Spicer.
Meanwhile, the president's cabinet continues to come together. Former South Carolina Gov. Nikki Haley has been sworn in as ambassador to the United Nations.
She supports the president's call to move the U.S. Embassy in Israel to Jerusalem.
Rethinking US's United Nations Role
Meanwhile, reports indicate, the Trump administration is considering drastically reducing the United States' role in the U.N.
Those cuts would be to the U.N. or any agency that give full membership to the Palestinian authority, support programs that fund abortions or go around sanctions against Iran or North Korea.
The US pays twenty-two percent of the UN budget.