The change was made under the revised Parental Leave (EU Directive) Regulations 2013, which were originally due to come into effect in March 2012.
Paul Griffin, head of the employment division at Norton Rose, said: “It is difficult for employers to arrange cover if parental leave is split into different chunks.
The extension of the right to unpaid parental leave followed the government’s introduction of the Children and Families Bill into Parliament on 4 February 2013.
The Bill proposes that, by 2015, working parents will be able to share parental leave after a child’s birth; prospective parents will be allowed to take more time off for antenatal appointments; leave and pay entitlements for adoptive parents will be aligned more closely with those for birth parents; and the right to request flexible working arrangements will be extended to all employees.
Jonathan Chamberlain, employment partner at Wragge and Co, said: “When shared parental leave comes in, the implications are potentially quite dramatic. There is a real incentive, for the first time, for fathers to take leave. The government could try to carve out contractual parental pay, but I think they will find that very difficult.”