Arcelor, the Luxembourg steel group, called an emergency general meeting for this Friday to vote on a share buy-back deal worth up to €5bn ($6.1bn). The move is part of Arcelor's defence against the €16.8bn hostile bid from Mittal Steel.

Arcelor said its shareholders had asked for the share buy-back option as a tax efficient way to receive the €5bn the company has promised to them if they repulse the Mittal bid within 12 months.