Bosses will be given new powers to tell older workers they should consider retirement without fear of being accused of ageism under plans unveiled today.
Nick Clegg said firms should be free to have "frank discussions" with underperforming staff, regardless of the employee's age.
The government proposal brought claims that companies could use the new law to force out older staff to save money.
TUC general secretary Brendan Barber said: "It would give a licence to bad employers to bully and intimidate staff."
But as he visited a hi-tech firm in Shoreditch, the Deputy Prime Minister said the move would allow people "to treat each other like human beings and not like potential litigants".
He added: "Employers tell us they're afraid to have frank discussions with staff ... for fear of those exchanges being used against them unfairly, should a dispute end up at tribunal.
"We want to give them the confidence to be open about performance, about retirement with their employees. If you speak to many employers, they value older workers massively. I don't think there is some sort of in-built prejudice against older workers at all."
At the moment, employees are able to use any comment or conversation to support their case in tribunals.
Supporters of the new measure say this leads to underperforming staff making notes of every remark or chat to bolster their defence, and creates a climate of suspicion between workers and bosses.
The proposed change means introducing a new law that will allow "protected conversations" - meaning staff will not be able to use them against employers later.
Mr Clegg denied claims that the idea could be used as a way to force older people out now that the default retirement age has been scrapped. He told the Standard: "If every employer and every employee thinks every informal conversation is going to be trawled through the tribunal system then of course it means people don't treat each other like human beings."
The plans for protected conversations have been drawn up by Liberal Democrat Business Minister Ed Davey. Aides insisted the new powers would not override employee protections under discrimination law.
Article from Evening Standard