In November 2018, the Pentagon filed a lawsuit after a US district court ruled that it was unreasonable for the country's Department of Defence (DoD) to order all green card holders to undergo full background checks.

The Pentagon plans to screen thousands of potential military recruits with green cards or other foreign ties over security concerns; the new policy will be shared with the military services by 15 February, according to DoD memos obtained by The Washington Post.

The Defence Department will specifically scrutinise prospective American military recruits who have spouses from other countries or family members with dual citizenship.

READ MORE: Man Accused of Trying to Infiltrate US Army to Commit Terrorism Pleads Guilty

Additionally, recruits who have non-US passports, have lived outside the country for more than three of the last ten years, or have financial interests abroad, will also be screened.

"One primary concern associated with qualifying for these positions relates to the potential counterintelligence or terrorism risks. […] The Department must implement expanded foreign vetting and screening protocols to identify and mitigate the foreign nexus risks," one of the memos read.

The plan will see the implementation of foreign nexus screening and vetting (FNSV), the process in which potential recruits will be closely scrutinised to determine if they pose a national security threat. Applicants will not be able to attend recruit training until they are cleared.

READ MORE: 'Three-Sided Coin': Analyst Looks at Root Causes of Home-Grown Terrorism in US

Another memo pointed out that "it is imperative to treat the risk related to a foreign nexus in a similar fashion for any recruit or Service member, regardless of citizenship".

According to the memo, FNSV "can be completed in a matter of days or, depending on the analysis required for detected anomalies, in a few weeks, as compared to the months and years" related to the completion of traditional background checks.

The FNSV mechanism "can process up to 1,600 cases per day", the memo claimed.

READ MORE: Uproar as US Teacher Calls for Arrest of Disabled Muslim Child Over 'Terrorism'

The Pentagon's reported FNSV push comes after it lodged a lawsuit in November 2018 following a decision by Judge Jon S. Tigar of the US District Court for the Northern District of California, in which he ruled it is not reasonable for the DoD to order all green card holders to undergo a full background check.

Stephanie P. Miller, who oversees the Pentagon's recruitment policy and prepared one of the memos, warned that if the court does not scrap its ruling on FNSV, "the harm to the military and national security could be significant and irreparable".