Ahead of Valentine's Day, the contest for breaking the record for the world's longest kiss has started in Pattaya, Thailand.

For setting up this year's Guinness World Record for the world's longest continuous kiss, the participants will need to have their lips locked for more than 50 hours, 25 minutes and one second - the record set by a male gay couple in 2012.Last year, there were seven participant couples.

A total of nine couples are taking part in this year's competition. The couples locked lips on Tuesday, 12 February, to break last year's world record.

This is the third year of the competition wherein the participants do not get food or bathroom breaks. For the first three hours of the competition, even bathroom breaks are not allowed. In case of a bathroom breaks after three hours, the participants are expected to have their lips locked, and a referee would accompany them to the bathroom especially designed for this contest. If the contestants' lips separate, they will be disqualified. The contestants are only allowed to drink water through a straw during the competition.

For this year's competition, the oldest participant couple is aged 74 and 72 years old. They have been together for more than 50 years.

"We have been married for fifty years. We want to see if we can do it," Digital Spy quoted 74-year-old contestant Pannajet Yomjinda as saying.

"I'm not sure if we'll win because of our age but if we were younger, we would surely win," said his 72-year-old wife Suwanna Yomjinda, according to the report.

Last year's record holder, 29-year-old Thanakorn Sithiemthong said that though he and his partner would give their best to break their record.

Participants Bunjed Yomjinda (2nd L), 74, kisses Suwanna Yomjinda, 72, during an attempt to break the world record for the longest kiss in Pattaya, 150 km (90 miles) east of Bangkok February 12, 2013. Thai couples locked lips to break the Guinness Record of the world longest continuous kiss ahead of Valentine's Day on Tuesday. Nine couples aimed to continue kissing until Thursday, to break the previous record of 50 hours 25 minutes and 1 second, held by a Thai couple.REUTERS/Chaiwat Subprasom
Participants Bunjed Yomjinda (front L), 74, kisses Suwanna Yomjinda, 72, during an attempt to break the world record for the longest kiss in Pattaya, 150 km (90 miles) east of Bangkok February 12, 2013. Thai couples locked lips to break the Guinness Record of the world longest continuous kiss ahead of Valentine's Day on Tuesday. Nine couples aimed to continue kissing until Thursday, to break the previous record of 50 hours 25 minutes and 1 second, held by a Thai couple.REUTERS/Chaiwat Subprasom
Participants Bunjed Yomjinda (R), 74, kisses Suwanna Yomjinda, 72, during an attempt to break the world record for the longest kiss in Pattaya, 150 km (90 miles) east of Bangkok February 12, 2013. Thai couples locked lips to break the Guinness Record of the world longest continuous kiss ahead of Valentine's Day on Tuesday. Nine couples aimed to continue kissing until Thursday, to break the previous record of 50 hours 25 minutes and 1 second, held by a Thai couple.REUTERS/Chaiwat Subprasom
Participants Ekkachai Tiranarat, (centre R), 44, kisses Laksana Tiranarat, 33, during an attempt to break the world record for the longest kiss in Pattaya, 150 km (90 miles) east of Bangkok February 12, 2013. Thai couples locked lips to break the Guinness Record of the world longest continuous kiss ahead of Valentine's Day on Tuesday. Nine couples aimed to continue kissing until Thursday, to break the previous record of 50 hours 25 minutes and 1 second, held by a Thai couple.REUTERS/Chaiwat Subprasom
Participant Nont Wittayanuch, (centre L), 25, kisses Tanasook Ariyadech, 23, during an attempt to break the world record for the longest kiss in Pattaya, 150 km (90 miles) east of Bangkok February 12, 2013. Thai couples locked lips to break the Guinness Record of the world longest continuous kiss ahead of Valentine's Day on Tuesday. Nine couples aimed to continue kissing until Thursday, to break the previous record of 50 hours 25 minutes and 1 second, held by a Thai couple.REUTERS/Chaiwat Subprasom
Participants Kanokwan Arjkidkarn (behind, L), 22, kisses Krittirath Chaikum, 25, during an attempt to break the world record for the longest kiss in Pattaya, 150 km (90 miles) east of Bangkok February 12, 2013. Thai couples locked lips to break the Guinness Record of the world longest continuous kiss ahead of Valentine's Day on Tuesday. Nine couples aimed to continue kissing until Thursday, to break the previous record of 50 hours 25 minutes and 1 second, held by a Thai couple.REUTERS/Chaiwat Subprasom
Participants Kanokwan Arjkidkarn (behind, L), 22, kisses Krittirath Chaikum, 25, during an attempt to break the world record for the longest kiss in Pattaya, 150 km (90 miles) east of Bangkok February 12, 2013. Thai couples locked lips to break the Guinness Record of the world longest continuous kiss ahead of Valentine's Day on Tuesday. Nine couples aimed to continue kissing until Thursday, to break the previous record of 50 hours 25 minutes and 1 second, held by a Thai couple.REUTERS/Chaiwat Subprasom