Four countries who do not take back citizens who are in the US illegally will face sanctions, the Department of Homeland Security has warned.

Although the names of the countries have not been revealed, CNN has identified them as Cambodia, Eritrea, Guinea and Sierra Leone.

It means people from these countries could be refused visas while the dispute is ongoing.

They are among 23 countries previously identified, and while on the campaign trail last year President Trump hit out at a perceived lack of action.

People from the four countries, identified as Cambodia, Eritrea, Guinea and Sierra Leone, could have their visas refused in the dispute, officials have confirmed. Travellers are pictured waiting in a winding line to pass through customs and border control at John F. Kennedy Airport in New York

Acting DHS Secretary Elaine Duke sent a letter to the State Department last week identifying the latest four countries that could face the new penalties.

DHS spokesman David Lapan declined to discuss possible sanctions or the names of the four countries that could face additional sanctions, including denying visas.

The State Department and the DHS can sanction countries that do not cooperate with removals, but has only used that punishment authority twice in the past 15 years.

Among those who have been identified as problematic are are China, Cuba, Vietnam, Laos, Iran, Cambodia, Myanmar, Morocco, Hong Kong, South Sudan, Guinea and Eritrea.

On the campaign trail last year, President Trump said not enough was being done about states that refused to take back their citizens

In a campaign speech last year, Trump pledged: 'There are at least 23 countries that refuse to take their people back after they've been ordered to leave the United States, including large numbers of violent criminals.

'They won't take them back. So we say, 'OK, we'll keep them'. Not going to happen with me, not going to happen with me.'

A statement from the DHS to CNN said: 'When we receive such notification, the law requires a suspension of visa issuance.

'We follow a standard process to implement a visa suspension as expeditiously as possible in the manner the Secretary determines most appropriate under the circumstances to achieve the desired goal.

'That process includes internal discussions with, and official notification to, affected countries. We are not going to get ahead of that process. When we have completed the process, information will be available about the terms of the visa suspension.'

In two cases since 2000, the United States halted issuing visas to government officials and their families to Guinea and Gambia. Lapan said in some cases the DHS has no choice but to release some convicted criminals who served prison time but could not be returned to their home country because their home country refuses to cooperate.

'We have tens of thousands of individuals,' Lapan said.

The DHS identifies countries that can be sanctioned and the State Department decides what, if any, sanctions could be imposed.

The DHS has said that it has final deportation orders against 35,000 Cuban citizens that have criminal histories that Cuba refuses to accept. (Reporting by David Shepardson and Eric Walsh; Editing by Paul Tait)