Union officials from Bectu, Amicus and the National Union of Journalists issued an ultimatum last month calling for a 90-day moratorium on job cuts, a bar on compulsory redundancies and protection of pay rates for staff facing privatisation or outsourcing.
BBC management had until April 4 as the deadline to respond, but put back this date and invited union officials to a face-to-face meeting with Thompson instead to thrash out their demands.
If negotiations are not resolved today, then the unions will hold a strike ballot across the BBC, which could lead to major disruption to BBC programming and affect its coverage of the May 5 General Election.
Last month, Thompson announced an extra 2,050 jobs will be lost on top of the 1,500 that were expected after December's wide-reaching review.
The unions do not believe that there is a need for such large-scale cuts. The BBC has been accused of rushing through the job cuts in an effort to placate the government in the wake of the Hutton Report in order to receive a favourable Charter Review.
Thompson plans to save save £221m by 2008 to reinvest in programme making and preparing the BBC for digital switchover.
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