Lorries are causing tailbacks as they travel to Newcastle

Deputy Chief Constable Peter Walker said the force was already "extremely stretched" because of flooding in the county.

"In over 25 years service I have policed many demonstrations and I have always made sure people have the opportunity to make their point," he said.

"Just this once I am asking them to leave us to deal with the crisis in Selby, York and Malton."

The convoy is set to arrive in London on Monday, to protest against Chancellor Gordon Brown's refusal to slash fuel tax in his pre-Budget statement.

Disappointed with cuts

Mr Brown moved to meet concerns of the fuel protesters by freezing duty on petrol and cutting duty on green fuels, but stopped way short of delivering the 26p a litre cut lorry drivers and farmers had been hoping for.

Following the announcement, David Handley, chairman of the People's Fuel Lobby, told the BBC: "It is not the cut we were looking for, it's not a cut right across the board."

Cuts on duty on the more environmentally friendly ultra-low sulphur petrol and diesel of up to 3p a litre would take some time to filter down to the average motorist, Mr Handley said.

The �715 average off road tax... well we'll wait and see how that pans out

PFL member

But the government says the new fuel should be available for motorists across the UK within the next few months, with the chancellor hoping it will account for 100% of petrol and diesel sales by next year.

Mr Handley said the convoy was travelling to London to ask the government to explain why it could not do more for hauliers.

It follows a 60-day moratorium laid down by the protesters after the September oil refinery blockades.

Last time the fuel protesters demonstrated in the capital there was traffic chaos, and in their blockades which took place in September much of the country was brought to a standstill.

'Wait and see'

But there was some faint praise for the chancellor from some members of the PFL, with Robbie Burns in Scotland saying: "I welcome the three-pence cut in fuel, that's as much as I could have hoped for, to be truthful.

"The �715 average off road tax... well we'll wait and see how that pans out."

And turning to the 'Brit disc' to be brought in for foreign lorries entering the UK, Mr Burns said: "I'll be waiting with interest to see what price he's going to charge them for coming in to our country and taking the work of the British and Scottish hauliers."

In his speech in the Commons the chancellor also announced that as well as freezing duty on red diesel, he would abolish vehicle excise duty on tractors and other agricultural vehicles.