Couples in Thailand have locked lips to try and break the record for the world's longest kiss.

Six couples attempted the record, which sees them unable to separate, or move outside of a marked 1m square box.

Each is competing not only for the record, but for a $3,300 diamond ring and a $6,600 holiday, although that will be no easy task as the record stands at an impressive 46 hours, 24 minutes and nine seconds.

That does not seem to phase the contestants though, with organisers confident someone will go the distance.

"We're sure to break the record and all six couples seem to have confidence at a hundred percent to make the new world record," said Somporn Naksuethrong, General Manager of Ripley's Pattaya.

Amongst the competitors are the current record holders, Lakkana Tiranarat and her husband, who set their previous best in 2011.

The 31 year-old hopes to beat her time: "We'll try to do better than last year but maybe just for a little longer. We have to see how tough the other competitors are but we'll do our best," said Lakkana.