Currently, employees need to have been in a role for a minimum of two years before they are entitled to protection from unfair dismissal.
Labour had planned to abolish this qualifying period completely, alongside a new legal probation period to be determined after a consultation.
The promise was a central pledge in Labour’s manifesto ahead of last year’s general election, and a key plank of its Employment Rights Bill.
But in recent weeks the House of Lords has twice voted in favour of a six-month period, slowing the legislation’s passage through Parliament.
The Conservatives called the U-turn “humiliating” but added that the legislation was “still not fit-for-purpose”.
“Keir Starmer must grow a backbone, stand up to his union paymasters and ditch every single job-destroying anti-growth measure in the employment rights bill now,” added shadow business secretary Andrew Griffith.