AGL rejects initial takeover bid from billionaire Mike Cannon-Brookes - but for investors it's "game on"

AGL shares have surged more than 11 percent after the company rejected an initial takeover bid from tech billionaire Mike Cannon-Brookes and Brookfield Asset Management. 

AGL's board says the audacious offer undervalues the company and is not in the interests of shareholders.

 But Mr Cannon-Brookes tells ABC's Peter Ryan AGL should reconsider what he calls a "compelling offer" to take the energy giant into the new green economy.