Trump 2nd term updates: Trump says USAID is run by 'radical lunatics'

Episcopal Church leaders on Tuesday released a letter urging Trump to "exercise mercy" in his approach to immigration policy.

While the service Trump is currently attending incorporates many faiths, the National Cathedral itself is part of the Episcopal Diocese in Washington.

"Even as we gave thanks for a peaceful transfer of power, we learned from news reports that the new presidential administration has issued a series of executive orders that are a harbinger of President Trump’s pledge to deport undocumented immigrants at a historic scale, restrict asylum, and direct other immigration actions," the church leaders wrote in a letter.

"We read this news with concern and urge our new president and congressional leaders to exercise mercy and compassion, especially toward law-abiding, long-term members of our congregations and communities; parents and children who are under threat of separation in the name of immigration enforcement; and women and children who are vulnerable to abuse in detention and who fear reporting abuse to law enforcement."

President Trump and Vice President Vance are attending an interfaith prayer service at Washington National Cathedral.

It's the first public appearance for Trump since Monday night's inaugural festivities.

First lady Melania Trump, second lady Usha Vance and Trump's children are there as well.

House Speaker Mike Johnson and Republican Rep. Mike Lawler are some of the lawmakers in attendance.

Standing alongside his cabinet ministers, Prime Minister Justin Trudeau addressed President Trump’s proposed tariffs, stating firmly that if the U.S. proceeds with the measure, Canada will not hesitate to respond in kind.

"Everything is on the table," Trudeau said adding, "We are prepared for every possible scenario."

-ABC News' Aleem Agha

Mexican President Claudia Sheinbaum responded to Trump's various decrees issued after the inauguration in a point-by-point statement.

Sheinbaum said Trump's decrees concerning the emergency zone of the southern border and the Migrant Protection Protocols were no different than the orders made during Trump's first term.

"We will always act in the defence of our independence, the defense of our fellow nationals living in the U.S. We act within the framework of our constitution and laws. We always act with a cool head," she said in her statement.

Sheinbaum however pushed back on Trump's decree to rename the Gulf of Mexico.

"For us and the whole world, it is still the Gulf of Mexico," she said.

-ABC News' Anne Laurent and Will Gretsky