The Argentine government has acknowledged that it lacks the proper technology to salvage the submarine that disappeared a year ago with 44 crew members onboard, after it was found on the seabed deep in the Atlantic early on Saturday.

Argentina’s defence minister, Oscar Aguad, said at a press conference that the navy doesn’t have submersibles with “modern technology” capable of “verifying the seabed” to extract the ARA San Juan, which was found 800 metres (2,625ft) deep in waters off the Valdes peninsula in Argentine Patagonia.

Aguad said that officials still need to determine what their next move will be.

Earlier in the morning, the navy said a “positive identification” had been made by a remote-operated submersible from the American company Ocean Infinity. The company was commissioned by the Argentine government to search for the missing vessel.

Part of the wreckage of the ARA San Juan submarine located one year after it vanished into the depths of the Atlantic Ocean. Photograph: HO/AFP/Getty Images

The discovery was announced two days after families of the missing sailors held a commemoration, one year after the sub disappeared on 15 November 2017.

On Thursday, the anniversary of the disappearance, Argentina’s president, Mauricio Macri, said the families of the submariners should not feel alone and delivered an “absolute and non-negotiable commitment” to discover the truth about what happened.

Macri promised a full investigation after the submarine was lost. Federal police raided naval bases and other buildings last January as part of an investigation, soon after the government dismissed the head of the navy.

The San Juan was returning to its base in the coastal city of Mar del Plata when contact was lost after it reported an electrical fault. Argentina gave up hope of finding survivors after an intense search aided by 18 countries, but the navy had continued searching for the vessel.

The German-built diesel-electric TR-1700 class submarine was commissioned in the mid-1980s and was most recently refitted between 2008 and 2014. During the $12m (£9m) retrofitting, the vessel was cut in half and had its engines and batteries replaced.

Experts said refits can be difficult because they involve integrating systems produced by different manufacturers, and even the tiniest mistake during the cutting phase can put the safety of the ship and crew at risk.

The navy said previously that the captain reported water had entered the snorkel and caused one of the sub’s batteries to short-circuit. The captain later communicated that it had been contained.

Hours later, an explosion was detected near the time and place where the San Juan was last heard from. The navy said the blast could have been caused by a “concentration of hydrogen” triggered by the battery problem reported by the captain.