United States President Donald Trump on Wednesday is expected to sign the order that will start the process of building a wall along the Mexico border. “Big day planned on national security tomorrow [Wednesday]. Among many other things, we will build the wall!” he tweeted. The other “big” plans for the day include changing immigration and border security rules that will restrict access to refugees, particularly Muslims, reported BBC.

A key poll promise of Trump’s was building a 2,000-mile wall along the US-Mexico border. Earlier this month, he had reiterated his stand on the matter. During a press conference on January 11, Trump had said, “I don’t wanna wait. [Vice-President-elect] Mike Pence is leading an effort to get final approval.”

Trump has time and again claimed that Mexico will pay for the wall. “Mexico in some form will reimburse us...that will happen,” he had said. But, Mexican President Enrique Pena Nieto had firmly said that his government would not pay for it. Trump’s adviser James Carafano told The Guardian that the US government will have to initially pay for the wall. The cost of the construction is estimated to be around $8 billion (Rs 53,000 crore).

Regarding immigration policy, Trump is likely to introduce steps that will compel the “sanctuary cities” in US to deport illegal immigrants. The businessman-turned-politician is expected to announce immigration restrictions from seven African and Middle Eastern countries later this week, according to BBC.

However, Carafano told BBC, “If they’re based on security concerns, of course they have nothing to do with a person’s actual religion,” he told BBC. Trump had earlier said they would deport as many as three million undocumented immigrants from the country upon assuming office.

Separately, Trump has asked the Environmental Protection Agency and the Department of Agriculture not to “providing updates on social media or to reporters,” reported Associated Press. The two federal agencies are also not allowed to award new contracts or grants.