Samsung Electronics on Monday said its months-long probe into what caused some Galaxy Note 7 smartphones to catch fire has established that faulty batteries were the main problem, not the device's hardware design or software.

"Our investigation, as well as investigations completed by three independent industry organisations, concluded that the batteries were found to be the cause of the Note 7 incidents," the South Korean tech giant said in a statement.

Samsung decided to discontinue the Note 7 last October after recalling millions of the devices worldwide over safety concerns, media reported.

"Nonetheless, we provided the target for the battery specifications for the innovative Note 7, and we are taking responsibility for our failure to ultimately identify and verify the issues arising from the battery design and manufacturing process prior to the launch of the Note 7."

Samsung said design and manufacturing issues related to the batteries were blamed for the Note 7 fires, but additional investigations were needed to find the root cause of the battery problems.

The conclusion came after about 700 Samsung researchers and engineers replicated the incidents by testing more than 200,000 fully-assembled devices and more than 30,000 batteries, it said.
   

Koh Dong-jin, head of Samsung's smartphone business division, apologised over the Note 7 recall and vowed to regain trust from consumers around the world.

During a press conferenceon Monday, Koh said the company has "taken several corrective actions to ensure this never happens again, including the implementation of a multilayer safety measures protocol at the product planning stage, and an 8-point Battery Safety Check."

The Note 7 recall cost the company about $5.3 billion, according to estimates.

While Samsung is trying to limit the damage done by the Note 7 recall, the company is developing its next flagship smartphone, the Galaxy S8, media reported.

However, it has no plans to unveil the S8 at the Mobile World Congress show in Spain next month, Koh said.

Meanwhile, the state-run Korean Agency for Technology and Standards, a government body in charge of technology standards, will release the results of its investigation into the Note 7 fires as early as this week or early next month, officials said.