Actually, he will be drinking a glass of fruit juice, because to eat immediately would be dangerous. He has lost 19kg.

The 29-year-old Melbourne university student stopped eating on November 6, along with seven other people around the world, including fellow Australian Anna Keenan, who is in Copenhagen. The group, calling themselves Climate Justice Fast!, demand urgent action on climate change.

Mr Connor, who founded the strike, said he was ''dismayed'' at the outcome of the United Nations Climate Change Conference.

''What has happened at Copenhagen is so far away from what's required. On the one hand, they're talking about keeping warming to two degrees, on the other hand their targets send us way beyond that,'' he said.

''The headline from [Barack] Obama is 'meaningful agreement', but you have the leader of Bangladesh going, 'Hang on, that's going to make 20 million refugees by the end of the century'.''

Although disheartened by the outcome, he said he had been ''deeply inspired'' when 10,000 people around the world joined in the fast, for a day, on Thursday.

Mr Connor slept at a supporter's house at Red Hill, where he even cooked a meal.

Most people visiting Parliament House had been supportive, he said, but some people had called out ''Get a job'' from a passing car, while others had suggested he must have been eating.

''Even if I'd been here every night, people would still be skeptical,'' he said.

The hardest part, physically, had been a couple of days of diarrhoea this week. ''Mentally, I got a bit short-tempered with supporters early in the fast, and on some days I had to ask visitors to leave me alone, because I felt so tired.''

For more, pick up a copy of today's Canberra Times