Ok, thanks!
I have tried now to assign it and it is not possible although it is written in the Manual (“Surface output in Abaqus/Standard and Abaqus/Explicit” in “Output to the output database,” Section 4.1.3) it can't be applied for general contact. I have tried to use Interaction domain in field output and it doesn't offer me the general contact interaction as a option to choose. I am talking about CAE, and it is written it is possible in CAE.