All judges sitting in family courts in England will be able to order DNA tests to determine a child’s true parentage from September.
Justice Minister Simon Hughes has announced the move following two pilot schemes in Taunton and Bristol.
They were set up following complaints that arguments over parenthood led to delays in divorce cases.
Mr Hughes said: “I am determined that all cases involving children should be resolved quickly and wherever possible outside court.
“However when they do come to court they should be resolved in a civilised way so that children don’t suffer.
“Unambiguous and conclusive DNA tests will prove parentage and help to end acrimonious and embarrassing court battles.”
The findings from the pilot suggest that the tests would give judges more confidence when making decisions about children.
It also found that parents would be more likely to follow the court’s orders.
Liz Cowell, family lawyer at Slater and Gordon, said: “This will assist in those cases where mothers try to allege that the father has no right to contact because he is not the natural parent.
“The change will also assist in cases where paying parents try to dodge supporting their children with claims that they are not the biological father.”
The paternity tests are expected to cost between £500,000 and £1 million a year.
Funding will come from the budget of the Children and Family Court Advisory and Support Service (Cafcass).