President Donald Trump has wanted to use the military to go after Latin American drug gangs that have been designated as global terrorist organisations.

The sources said the ships are the USS Gravely, USS Jason Dunham and the USS Sampson.

A separate US official told Reuters that in total, about 4,000 sailors and Marines are expected to be committed to the Trump administration’s efforts in the southern Caribbean region.

That US official, who was speaking on the condition of anonymity, said the additional commitment of military assets in the broader region would include several P-8 spy planes, warships and at least one attack submarine.

The official said the process would be ongoing for several months and the plan was for them to operate in international airspace and international waters.

The naval assets can be used to not just carry out intelligence and surveillance operations, but also as a launching pad for targeted strikes if a decision is made, the official added.

Trump has made cracking down on drug cartels a central goal of his administration as part of a wider effort to limit migration and secure the US southern border.

The Trump administration in recent months has already deployed at least two warships to help in border security efforts and drug trafficking.

The Trump administration designated Mexico’s Sinaloa Cartel and other drug gangs, as well as Venezuelan criminal group Tren de Aragua, as global terrorist organisations in February, as it stepped up immigration enforcement against alleged gang members.

The US military has already been increasing its airborne surveillance of Mexican drug cartels to collect intelligence to determine how to best counter their activities.