President Donald Trump has confirmed on Twitter he will proceed with a Mexico-border wall ahead of national security announcements tomorrow (US time).

Mr Trump tweeted around 12.30am Thursday (US time) about the impending “big day on NATIONAL SECURITY”, adding that the wall would be part of announcements.

Big day planned on NATIONAL SECURITY tomorrow. Among many other things, we will build the wall!

— Donald J. Trump (@realDonaldTrump) January 25, 2017

Mr Trump is also expected to sign executive orders that include a ban on most refugees and a suspension of visas for citizens of Syria and six other Middle Eastern and African countries, congressional officials say.

Mr Trump is expected to order a multi-month ban on allowing refugees into the US except for religious minorities escaping persecution, until more aggressive vetting is in place.

Another order will block visas being issued to anyone from Syria, Iraq, Iran, Libya, Somalia, Sudan and Yemen, the officials said.

The sources have said the first of the orders will be signed on Wednesday.

But Mr Trump is also considering measures to tighten border security and could turn his attention to the refugee issue later this week.

The border security measures could include directing the construction of a border wall with Mexico and other actions to reduce the number of illegal immigrants living inside the US.

A Mexican, anti-Trump activist places a Mexican flag on a Trump cut-out on the National Mall this week. Photo: Getty.

The Republican president, who took office last Friday, was expected to sign the first of the orders at the Department of Homeland Security, whose responsibilities include immigration and border security.

On the campaign trail, Mr Trump initially proposed a temporary ban on Muslims entering the US, which he said would protect Americans from jihadist attacks.

Both Mr Trump and his nominee for attorney-general, US Senator Jeff Sessions, have since said they would focus the restrictions on countries whose migrants could pose a threat, rather than place a ban on people who follow a specific religion.

Many Trump supporters decried former President Barack Obama’s decision to increase the number of Syrian refugees admitted to the US over fears those fleeing the country’s civil war would carry out attacks.

Protesters against Donald Trump after a speech on Islamic migration in 2016. Photo: Getty.

Detractors could launch legal challenges to the moves if all the countries subject to the ban are Muslim-majority nations, said immigration expert Hiroshi Motomura at UCLA school of law.

To block entry from the designated countries, Trump is likely to instruct the State Department to stop issuing visas to people from those nations, according to sources familiar with the visa process.

Other measures may include directing all agencies to finish work on a biometric identification system for non-citizens entering and exiting the US and a crackdown on immigrants fraudulently receiving government benefits.

Mr Trump is also expected to take part in a ceremony installing his new secretary of homeland security, retired Marine General John Kelly, on Wednesday.

– with AAP