The BBC's Alan Powell: "The minimum wage is welcome, but not enough"

Police said the march, organised by public sector union Unison and backed by 20 unions, attracted 10,000 people. This was half the number expected.

A national minimum hourly rate of £3.60 for adults and £3 for 18- to 21-year-olds was introduced on 1 April - the first minimum wage in British history.

Although unions have fought long and hard for a national base rate, many are unhappy with the level at which it has been set and say it is does not amount to a "living wage".

"Whilst we are delighted that we have for the first time, after a 100-year battle to get it, a minimum wage, that level is far, far too low," said Unison's general secretary, Rodney Bickerstaffe, who took part in the march.

He said the north east was chosen because it was an area of low pay.

Bickertsaffe: "Level is too low"

"The argument that a higher minimum wage will cost jobs doesn't stand up in an area like the north east which has always suffered high unemployment," he said.

The Federation of Small Businesses said Mr Bickerstaffe was "barking up the wrong tree" by calling for an increase in the minimum wage.

FSB employment spokesman Bernard Juby said: "Mr Bickerstaffe should realise that the money for the wages has to come from somewhere. It's cloud-cuckoo land to believe that it simply grows on trees."

Hairdressers losing jobs

The government is unlikely to take a decision on whether or not to raise the minimum wage until it is clear how many jobs have been lost as a result of its introduction.

Some predictions suggested that as many as 80,000 low paid workers could be laid off by employers who could not afford the £3.60 rate. Early indications suggest these figures were too high.

But unions have already begun to report that workers in some industries are losing their jobs, particularly in hairdressing.