One of US retail giant Gap Inc's Canadian stores was on Tuesday targeted by a group of naked anti-globalisation protestors who accused the company of selling apparel made in overseas sweatshops.

About 20 people took part in the noisy but non-violent protest outside Gap's downtown Calgary store. Hundreds of protestors have gathered in the city ahead of this week's G8 summit.

The demonstration was broken up by police while Gap strongly denied claims it buys clothing made by exploited workers in less-developed countries.