Marconi had been expected to produce a new business plan and comment on the progress of talks to restructure its £2.2bn in syndicated loans and £1.8bn in bonds. However, on Wednesday the group said it would not update the market on progress because the talks had entered a new phase. Shares in the group, which was worth about £35bn at the peak of the technology boom, led the FTSE 250 fallers, shedding 16%, or 1.45p, to only 7.65p.