Big Issue, the magazine set up to help the homeless, is seeking to reduce staff numbers after the advertising slowdown hit income.

The magazine is scaling down its London office, where it has received six applications for redundancy from its 13 journalists.

The shake-up comes amid a cash squeeze prompted by the advertising downturn which has hit all publishers, founder John Bird said.

But he denied a report that the magazine was facing its most severe crisis in its 11-year history.

"The Big Issue, unlike charities, set out its stall in the marketplace and rises and falls in the marketplace," he told BBC News Online.

"We are determined to see the Big Issue survive and prosper."

The magazine sells an average of 300,000 copies a week, with sellers, drawn from the ranks of the homeless, keeping the difference between, typically, the 40p cost price and the �1.20 cover price.

Global aims

The revamp will see production focused on Manchester, with greater pooling of copy between the five UK Big Issue editions.

"If you are receiving less income from advertising, it only makes sense to make some economies and start sharing copy from other Big Issues," Mr Bird said.

The shake-up is also being used as an opportunity to encourage greater input from similar publishing houses abroad, many of which have been set up with the Big Issue's help.

"I am an internationalist. Homelessness is an international issue," he said.

"The Big Issue was set up as part of an international movement. Isn't it fair that this should be reflected in the magazine's content?"

The aftermath of the 11 September attacks had illustrated how many "abject poor" were living in cities in the US, where the Big Issue in 1998 opened a Los Angeles operation.

"Why can't we learn from them," Mr Bird said.

'Good time to go'

While journalists leaving the Big Issue face finding new work in an uncertain media market, Mr Bird said the degree of change at the business had prompted the six to seek voluntary redundancy.

"We are going through this change. We said if anyone wanted to jump, this was probably a good time."

The magazine had always been relaxed about staff turnover, seeing itself as a training ground for journalists seeking jobs on national newspapers, he added.