Manchester United and Liverpool supporters who are caught unfurling obscene banners this weekend could face jail.

The pair's last meeting at Old Trafford - a Europa League quarter-final in March - was blighted by abhorrent chanting and fighting.

That came after a Hillsborough banner, reading 'murderers' alongside the date of the tragedy, was draped over a motorway bridge.

A controversial banner relating to the 1989 Hillsborough disaster was unfurled on the M602 ahead of Liverpool's trip to Manchester United during their Europa League tie in March

Manchester United fans were greeted by a few rude banner hanging from M62 motorway bridge ahead of the first leg of the Europa League encounter at Anfield

It was in full view of travelling fans driving through Salford on the way to Old Trafford, with two men ordered to serve community service for posting the pictures online.

Sportsmail understands that fans found to have made or displayed any repugnant signs and subsequently tried could face custody under the Communications Act 2003.

Sources claim punishment ranges from a fine to prison depending on the seriousness of the case.

Greater Manchester Police are treating the Premier League clash as they normally would a match which carries the highest security risk rating.

Drink on the city centre and Trafford streets will be banned ahead of the 4pm kick-off, with fans to be searched on entry.

Hundreds of officers will be deployed and there is a hope the afternoon passes without incident, as during the stalemate at Anfield earlier this season.

They had earlier been warned that anybody singing about the Hillsborough or Munich disasters would be immediately thrown out in October. Both sets of supporters were later praised by police for their 'exemplary behaviour'.

Superintendent Dean Howard, match commander for Sunday's game, said: 'I would like to welcome all supporters from both clubs ahead of what is traditionally one of the most competitive fixtures of the season.

The M602 between Liverpool and Manchester will be used by travelling supporters

Liverpool and Manchester United played out a goalless draw at Anfield earlier this season

'We have extensive experience policing high-profile matches such as this, with numerous high-category games taking place every season, and we will have a full operation in place on the day to ensure the safety of all those in attendance.

'The aim of our operation is not to hamper the lively atmosphere that fixtures like this create but to ensure that all those in attendance can enjoy the game in a competitive and safe environment.

'However we will be prepared to take swift action against those who take part in any incident of disorder and put the well-being of others at risk.

'There will be a visible police presence on Sunday so if anybody has any concerns then I would urge them to approach one of our officers or a club steward who will be happy to assist.'