An Australian man whose girlfriend was killed when their jet skis collided in Thailand has pleaded guilty to a charge of recklessly causing death.

Thomas Keating, 21, arrived at Karon provincial police station in Phuket, flanked by members of his family and relatives of Emily Collie, who died in the crash.

“Thomas pleaded guilty,” Superintendent Sanya Thongsawad told the ABC.

Police said it was the first time Keating had ridden a jet ski.

The couple were “having fun”, trying to splash each other when their crafts collided, leaving Ms Collie with serious neck and shoulder injuries.

Lifeguards tried unsuccessfully to revive her on the beach.

Ms Collie’s family released a statement saying they did not blame him for the tragic accident and wished to grieve together.

“We do not place any blame on Tom Keating, who we care about very much and who we know loved Emily deeply,” a family statement said.

“We are all heartbroken beyond words, and at this extremely sad time, we wish to be together with our family, with Tom, and with other loved ones to grieve and celebrate Emily’s life.”

Keating posted an emotional message on social media this week, saying he felt “broken” and would “never be able to mend”.

“I love you so much Emily, and I wish I could just bring you back into my arms,” he wrote.

“Fly high up there Emmy, I know you’ll always be looking down on me and everyone you loved.”

“Police don’t have to detain him but he is now banned from leaving the country until the court process is completed,” Superintendent Sanya said.

A prosecutor will now prepare a case, which is expected to take around two weeks.

Under Thai law, the offence is punishable by up to 10 years in jail.

Ian and Sally Collie acknowledged their daughter’s death was “a tragic accident” and that they “do not believe anybody was at fault”.

“We do not place any blame on Tom Keating, who we care about very much and who we know loved Emily deeply,” a family statement said.

“We are all heartbroken beyond words, and at this extremely sad time, we wish to be together with our family, with Tom, and with other loved ones to grieve and celebrate Emily’s life.”

While the case may go to court, police suggested a suspended sentence was a likely outcome.

“Relatives from both sides are here,” Superintendent Sanya said.

– ABC