A former plasterer's non-stop swim around a Greek island to raise money to clear up marine litter has been held up by stormy weather.
Oly Rush, from Upton in Dorset, had been due to set off on the 24-hour swim around Ithaca on Monday.
"There's thunderstorms and lightning, it wouldn't be safe to be out on the water", he said.
He hopes to raise £15,000 from the 37-mile (60km) swim to fund beach cleans along the Dorset coastline.
He hopes to start on Friday or Saturday once the storm had passed.
"We're going to get the swim done one way or another but we obviously need to go in safe conditions", Mr Rush said.
The swim, a record attempt to be the fastest person to lap the island, means he has to stay in the water and cannot come into contact with anyone.
Accompanied by a boat and a kayak, he says food and drink will be "chucked to me on a bit of string in an old milk bottle container which I then chuck back".
He said he hoped to complete the swim in the Ionian Sea which he expects to pose some problems, including jellyfish, with spotters on his support boat looking out for them.
Costs for the record attempt have been funded by a Hampshire firm and through support from volunteers.
Mr Rush said he had also been offered accommodation on the island by its mayor after he heard about the charity challenge.
His previous swims include the length of the Jurassic Coast, a 100-mile swim in 2020.
He also became the fastest person to swim around the Isle of Wight in August 2021, completing a 65-mile (105km) lap in 15 hours and nine minutes.
Last summer he was the first person to swim around Grand Cayman non-stop.
To date, his environmental conservation organisation Project Planet Earth has raised more than £56,500 to support projects cleaning up plastic in coastal areas.