The British government has asked that property owners either remove or trim branches from ash trees that are suffering from dieback fungus.

If the trees are not dealt with, property owners could face lawsuits if someone is injured by a falling branch or tree, The Daily Telegraph reported Monday.

Ash dieback has been found at 257 sites around the country and experts say it will gradually spread to most of the United Kingdom's 92 million ash trees.

Mike Seville, the forestry and woodland adviser at the Country Land and Business Association, said it will cost about $800 to make trees safe by employing tree surgeons to take off branches or fell trees.

"As the tree falls to pieces there is going to be some significant costs," Seville said.