The Government has come under attack from both sides of industry after confirming plans for mothers and fathers to share parental leave.
Measures are also expected to expand the right to request flexible working to all employees, not just those with children under the age of 17, although no new details have been given.
The Government said that under its Children and Families Bill, mothers and fathers can share caring responsibilities. The idea was raised last year and a consultation was held, with the Government due to make its response shortly, for implementation in 2015.
John Longworth, director general of the British Chambers of Commerce, warned of "complex new burdens" around shared parental leave.
He said: "Ministers have chosen to ignore the fact that a complex new system of shared parental leave brings fiendish complexity and huge uncertainty for employers across Britain. These proposals will hit business at precisely the time ministers are asking companies to create jobs and spur growth.
"While most businesspeople identify with the idea of gender-neutral parental leave, they've warned time and again that the Government's proposals are unwieldy, difficult to understand and fraught with potential complications. Businesses may now be exposed to endless appeals, legal challenges and grievances."
TUC general secretary Brendan Barber said: "Of course, any modest increase in rights to request flexible working is welcome but this should not obscure the fact that this Government is taking the workplace backwards."
Sarah Jackson, chief executive of the Working Families charity, said: "We want to see more choice and flexibility for fathers to share the care and more paternity leave would be a great step forward, but the Government consulted on cutting maternity leave to 18 weeks which is a step too far.
"We're disappointed that there was nothing about extending flexible working rights in the Queen's Speech. Good employers already offer flexible working to all their employees because they know that it leads to high performance and reduces costs. We urge the Government to include an extension of the right to request flexible working in their programme to boost economic growth and help everyone get the work-life balance they need."
A Business Department spokesman said: "Parents should be able to choose their childcare arrangements for themselves. At the moment families are dictated to by an outdated system which presumes that women will take the vast majority of leave. We want to change that perception, bring flexibility into the decision, while at the same time making sure that businesses will still be able to take into account their needs when agreeing how leave can be taken."