Samsung has asked all retailers across the globe to stop selling and exchanging its Galaxy Note7 smartphone, and has instructed all owners of the phone to power it off and seek a refund or replacement.

The phone was originally recalled after a battery issue lead to several reported cases of overheating and combustion. In recent weeks there have been at least five cases of replacement Note7's also catching fire or overheating.

While the Korean company was recently reported to have stopped making Note7s as it investigated the reports, it has always been careful to state it believes the new phones are safe, or that the issue is "limited". In its latest statement on Tuesday morning, Samsung is more direct.

"Because consumers' safety remains our top priority, Samsung will ask all carrier and retail partners globally to stop sales and exchanges of the Galaxy Note7 while the investigation is taking place", the statement reads.