Adrian Flanagan will have to navigate past icebergs as he sails through some of the least-travelled seas during his 11-month challenge.

Mr Flanagan hopes to leave the Solent next month, heading south around South America, up through the Bering Strait and round northern Europe.

The 44-year-old announced his plans during Cowes Week on the Isle of Wight.

I am apprehensive but quite eager to get away Adrian Flanagan

He said he was embarking on the adventure to satisfy a life-long ambition as well as to raise money for three charities.

The voyage on the 11-metre yacht Barrabas will be a giant leap for the father-of-two, whose previous longest journey was across the Atlantic as part of the Times Clipper Race in 2000.

He said: "Nervous would be the wrong word to describe how I am feeling at the moment. I am apprehensive but quite eager to get away."

He said: "The most difficult part will be the north-west passage. That hasn't been done before as part of a circumnavigation or single-handedly.

"The ice melts differently there each year. I won't know until I get there whether I can get through safely, which adds an unknown quantity to the challenge."

Mr Flanagan hopes people will sponsor him to aid the charities Save The Children and the Alpha Global Tsunami Appeal and a fund for the new Oxford Children's Hospital.