If you secure an area with the Mordenkainen's private sanctum spell and choose the effect:
Planar travel is blocked within the warded area.
Does this prevent summoning creatures into the area via spells like infernal calling (XGtE, p. 158)?
Planar travel, in this instance, could either mean "willingly moving between planes" or "moving between planes under any circumstance", and I don't know which is meant by the spell.