British scientists have been granted permission to genetically modify human embryos by the fertility regulator.

The Francis Crick Institute could begin the controversial experiments as early as March after the Human Fertilisation and Embryology Authority (HFEA) gave the green light this morning.

The scientists want to deactivate genes in leftover embryos from IVF clinics to see if it hinders development.

It will only be the second time in the world that such a procedure has been undertaken and the first time it has been directly approved by a regulator. A Chinese team carried out similar experiments last year to widespread outcry.