The United States has lifted the ban on refugees from 11 “high-risk” countries – mostly West Asian and African – and will resume allowing refugees from these nations, officials said on Monday. However, these refugees will have to go through additional security screenings before being allowed to enter the US.

“We will be rolling out new security measures for applicants from high-risk countries, which will seek to prevent the programme from being exploited by terrorists, criminals and fraudsters,” US Homeland Security Secretary Kirstjen Nielsen said, according to The Guardian.

Officials did not explain what the extra vetting will entail for the refugees. The immigration programme will also include a periodic review of the list of countries the US believes poses greater security risks than others, Reuters reported.

The US administration lifted the ban after the departments of state and homeland security, along with intelligence agencies, reviewed the admission of refugees from the 11 countries – Syria, Sudan, South Sudan, Mali, North Korea, Somalia, Libya, Iran, Iraq, Yemen and Egypt – for 90 days. President Donald Trump’s executive order, which came into effect in October 2017, had led to a significant drop in the number of refugees entering the US.

In December 2017, a federal judge in the US had partially blocked Trump’s restrictions on refugees from these 11 countries. Seattle District Judge James Robart had ruled that the administration could carry out security reviews, but it could not stop processing or admitting refugees until then.