Speaking at a forum bringing together the CBI, large employers and online community Mumsnet which has campaigned for better  offerings for parents at work, Clegg said: 'It is bizarre that even in the 21st century, hundreds and thousands of employees are still restricted by Edwardian rules when it comes to juggling their work and family lives.’

At the event, Clegg welcomed news that accountancy firms would be amongst those to offer enhanced paternity package to all their employees, saying: ‘I’m delighted that Deloitte, PwC and Shell are taking positive steps in modernising the workplace by providing flexible working arrangements for hardworking parents.’

A PwC spokesperson said the firm is currently reconfiguring its package, but it currently equates to in excess of 20 weeks base pay.

Gaenor Bagley, executive board member and head of people at PwC, said: ‘We have always offered flexible working to all and will now offer fathers the same benefits we offer to mothers through our enhanced maternity package.

'I see this as being a critical move to level the playing field, and an integral part of PwC's strategy, to ensure that all of our employees have the same options and opportunities.’

Emma Codd, managing partner for talent at Deloitte UK, described support for working parents as ‘a firm-wide priority’ and said the firm’s plan to introduce enhanced shared parental leave (SPL) formed part of a bigger picture of practical help which was aiming to achieve a cultural shift. Deloitte’s SPL offering will match its current level of enhanced maternity and adoption pay, which allows 16 weeks at full pay, followed by 10 weeks at half pay.  

Codd said: ‘Beyond SPL, we are introducing additional enhanced parental policies, including paid time off for fathers and partners to attend ante-natal appointments, and for co-adopters to attend adoption appointments. Additionally, we’ll be offering those who become parents through surrogacy the same leave and pay entitlement as other parents.’

From 5 April 2015, new UK legislation will allow mothers, fathers, partners, and adopters to opt for SPL, to be taken up to a year after a child is born or adopted. Eligible parents will have the option to share a period of their maternity or adoption leave with their partner, including sharing statutory pay.

The government has said that such initiatives are critical to closing the gender pay gap, which has now shrunk to its lowest point in history, according to new data from the Office for National Statistics (ONS).

The ONS figures show that the overall gender pay gap has fallen by 0.7 percentage points over the past year to 19.1% - this includes all full- and part-time workers combined and reflects the fact that around 40% of women work part time. The gender pay gap for full time workers only has reduced by 0.6 percentage points to 9.4%, and is close to zero for those aged under 40.