Prebble will meet with Duncan Eaton, marketing and strategy director of Carlton Interactive, and Granada Broadband managing director Simon Shaps.
The creation of ITV.com is expected to result in some job losses, but the broadcasters expect to recoup £20m in savings through closer cooperation.
The plans by Carlton and Granada to consolidate their digital operations were unveiled late last month, when they announced a restructuring of the commercial station and a revamping and renaming of their joint-venture digital broadcaster ONdigital. At the same time, Prebble was named chief executive of ITV.
Meanwhile, ONdigital rivals Telewest and BSkyB have been lobbying TV watchdog the Independent Television Commission about ITV's plans to advertise the digital terrestrial broadcaster for free.
The ITC launched a consultation on cross-promotion rules last month and proposed that ITV be allowed to give airtime to its digital service between programmes, providing it made viewers aware that cable and satellite services are also available.
Telewest CEO Adam Singer has written to the regulator to protest about ITV's plans and has threatened legal action to prevent cross-promotion of ITV Digital on ITV.
Singer is accusing the ITC of favouring the commercial broadcaster but the regulator claims a relaxation of cross-promotion legislation could bolster the take-up of digital services.