Up to 50 funerals at Oxford Crematorium have been delayed because of roadworks at the city's biggest roundabout.

A small number of funerals at the crematorium, off Bayswater Road, have been delayed by as much as an hour because mourners have been caught in the traffic jams.

For Oxford-based funeral firms, the cortege has to cross the Green Road roundabout in Headington before it can drive through the Barton estate to reach the crematorium just outside the city.

Now, a week after a contraflow system was put in place on the A40 near the roundabout, they are seeking alternative routes and are advising mourners to do the same.

Lesley Leon, a spokesman for Dignity, which runs Oxford Crematorium, said: "Since late last week, a lot of mourners have been arriving late and that of course delays the starting time of funerals.

"Up to 50 funerals have been affected by significant delays, with some corteges being delayed by up to an hour.

"It's a very upsetting time for the families and, of course, if they are stuck in traffic it makes matters worse.

"All the funerals that are scheduled are going ahead because we would never turn people away, and we are now advising everyone to allow extra time for their journeys."

Sandra Homewood, senior partner for S&R Childs funeral directors in London Road, Headington, urged the county council to install traffic lights and carry out work at night.

She said: "Families are distressed enough as it is, and now they are having to sit in a traffic jam.

"The county council should put traffic lights on the roundabout during the day and continue the work at night to get it finished quicker.

"Our drivers are trying to use alternative routes, but all the rat-runs are congested now as well."

Lucy Jane, assistant funeral director at Reeves & Pain in Abingdon Road, said their drivers were taking "huge diversions" to avoid the ring road.

She added: "We did have a problem with one minister who didn't make it at all for a funeral because he was so late, and had to be replaced.

"He was devastated because the bereaved family were personal friends."

David Robertson, cabinet member for transport, said he sympathised with bereaved families.

He said traffic signals would not be installed on the roundabout until the second phase of work was completed, and that night work was not an option because it was not cost-effective.

He added: "We have been monitoring the traffic on a daily basis and using manual signals, and the situation has improved throughout the week.

"Our objective is to keep the roundabout clear. Those attending funerals are already going through a terrible time, so they should leave extra time for their journeys."

The roadworks, which include manually-operated traffic lights at peak times, will be in place for 10 weeks and will cover a 400-metre stretch on either side of the Sandhills junction.

Commuters have been seeking alternative routes through villages including Horspath, Wheatley and Garsington to avoid the jams.

The £3.75m redesign of the junction dubbed the hamburger will see the construction of a lane through the centre of the roundabout for westbound traffic on the A40.

Work is due to finish in December.