Media
Plans are at an early stage but Rupert Howell, managing director of ITV brand and commercial, said he wanted their identities to be "more precise".
ITV3 has become known for drama serials while ITV4 focuses on male-skewing documentaries and sport. However, Howell said both were "vaguer" than ITV2.
In May, the channels' share of viewing had increased year-on-year to 1.5% and 0.9% respectively. "It is a balancing act, although they are doing so well that we don't want to spoil that," Howell told Brand Republic.
Howell said the broadcaster would look to use the channels for shows "which can move on to ITV1".
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