Trump signs order on immigration and border wall

US President Donald Trump took a first step toward fulfilling his pledge to "build a wall" on the border with Mexico on Wednesday, signing two immigration-related decrees.

Trump visited the Department of Homeland Security to approve an order to "build a large physical barrier on the southern border," according to the White House.

Trump also signed measures to "create more detention space for illegal immigrants along the southern border," according to White House spokesperson Sean Spicer.

"We're going to once again prioritise the prosecution and deportation of illegal immigrants who have also otherwise violated our laws," he added.

Stemming immigration was a central plank of Trump's election campaign. His signature policy prescription was to build a wall across the 2,000-mile (3,200-kilometres) border between the US and Mexico.

Some of the border is already fenced, but Trump says a wall is needed to stop illegal immigrants entering from Latin America.

TRT World's Tetiana Anderson has more details.

In 2014, there were an estimated 5.8 million unauthorised Mexican migrants in the US, according to Pew.

Experts have voiced doubts about whether a wall would actually stem illegal immigration, or if it is worth the billions it is expected to cost.

TRT World spoke to Shika Dalmia, senior analyst at Reason Foundation, who says some of Trump's executive orders can't be implemented.

Rights advocates slam plans

Another controversial executive order the president is expected to sign this week places a temporary ban on refugees from several Muslim-majority countries, among other immigration restrictions.

Immigrant and refugee advocates denounced Trump's plans, saying they target Muslims and will make America less safe.

"The president needs to know he's an absolute fool for fostering this kind of hostility in his first few days. This will inflame violence against Americans around the world," said Seth Kaper-Dale, a pastor at the Reformed Church of Highland Park, New Jersey, which he said helped resettle 28 refugee and asylum-seeking families in the state last year.

Before his November 8 election victory, Trump pledged to stop taking refugees from Syria and immigrants from countries deemed to pose a terrorism risk.

"Muslims, we believe, are the sole targets of these orders," said Nihad Awad, executive director of the Council on American-Islamic Relations, a Muslim civil rights group.

"These orders are a disturbing confirmation of Islamophobic and un-American policy proposals made during the presidential election campaign," Awad told a news conference in Washington.