A teenage rugby player cut off his own penis and stabbed his mother while high on skunk, his father has revealed, as he called for the drug to be reclassified.

The father, named only as Nick because he wants to remain anonymous as his son is rebuilding his life, is backing Lord Nicholas Monson's campaign to have skunk reclassified from a class B to a class A drug and for the traditional weaker form of cannabis to be decriminalised.

Lord Monson launched his call following the suicide of his 21-year-old son Rupert, who was addicted to skunk.