Conservationists have called for an immediate mandatory ban on bringing ash trees into the UK to stop ash dieback, caused by the fungus Chalara fraxinea, becoming established here.

Without a compulsory ban on imports, ash die-back could become the new Dutch elm disease, causing widespread destruction of one of the country's most common native broadleaf trees, the Woodland Trust has warned.

The fungus, which causes leaf loss and crown dieback and can lead to tree death, has wiped out 90% of ash trees in Denmark in seven years and is becoming widespread throughout central Europe.

The disease was recorded for the first time in Leicestershire earlier this year. It has since been found elsewhere in England and in Scotland.

Last month, the Horticultural Trades Association announced a voluntary moratorium on importing the trees in a bid to stop the spread of ash dieback.

The Forestry Commission is conducting a consultation on controlling the disease, which closes on October 26, and the Environment Depart- ment said a ban could be in place as early as November before the autumn tree planting season gets under way.

Environment Secretary Owen Paterson said: "This disease could have a devastating impact on our native ash trees.

"By taking decisive action we can prevent our ash trees from suffering the same fate as elm trees did in the 1970s."

Norman Starks, UK operations director at the Woodland Trust, said: "This is not a minute too soon.

"The trust will no longer plant imported ash trees on our estate and is reducing the number of ash to be planted this season by 100,000 trees."