Five-time world champion Magnus Carlsen says it has become easy to cheat at chess, but he has stopped short of directly accusing a rival of doing so.

Carlsen sent the chess world into a spin this week by resigning from an online match against American teenager Hans Niemann after making just one move.

It was their first encounter since Carlsen pulled out of a tournament after losing to Niemann and posted a cryptic tweet that many felt insinuated the 19-year-old had cheated.

"I cannot particularly speak on that, but people can draw their own conclusion and they certainly have," Carlsen told chess24.

"I have to say I'm very impressed by Niemann's play and I think his mentor Maxim Dlugy must have been doing a great job."

Carlsen's reference to the American grandmaster Dlugy has been interpreted as another veiled swipe at Niemann.

Dlugy has also been accused of past foul play.

Niemann has vigorously denied the suggestion he cheated in his recent over-the-board win against Carlsen at the Sinquefield Cup, but has conceded he cheated in some online games when he was 12 and 16.

Carlsen believes receiving illegal assistance has become tempting for some players.

"Regardless of whether it’s a massive problem or not, I think it’s fairly easy to cheat," the Norwegian grandmaster said.

"It should not be taken lightly."

Carlsen said he would have more to say about the situation after the Julius Baer Generation Cup

"I'm just living my life and trying to do well in the tournament," he said.

"People who know me know I can sort of shut things off."