A method comprising: identifying, by a virtual network controller, a source logical router and a destination logical router implemented on one or more physical devices (104, 106) of a switch fabric, wherein the source logical router maintains routing information specifying routes for a first virtual network and the destination logical router maintains routing information specifying routes for a second virtual network, wherein the source logical router and the destination logical router reside on the same physical device of the one or more physical devices of the switch fabric; forming, by the virtual network controller, a logical router interconnect between the source logical router and the destination logical router, wherein forming a logical router interconnect comprises defining a routing information base, RIB, group that groups one or more routing tables of the source logical router and the destination logical router to form the RIB group; forming, by the virtual network controller, a unidirectional policy defining one or more rules for controlling leaking of one or more of the routes through the logical router interconnect from the source logical router of the first virtual network to the destination logical router of the second virtual network wherein forming a unidirectional policy comprises defining one or more rules specifying actions for the physical devices to apply, based on a community name or community member associated with the RIB group, to routes leaked via the logical router interconnect; and pushing, by the virtual network controller, the unidirectional policy to the one or more physical devices of the switch fabric for application to communications through the logical router interconnect. identifying, by a virtual network controller, a source logical router and a destination logical router implemented on one or more physical devices (104, 106) of a switch fabric, wherein the source logical router maintains routing information specifying routes for a first virtual network and the destination logical router maintains routing information specifying routes for a second virtual network, wherein the source logical router and the destination logical router reside on the same physical device of the one or more physical devices of the switch fabric; forming, by the virtual network controller, a logical router interconnect between the source logical router and the destination logical router, wherein forming a logical router interconnect comprises defining a routing information base, RIB, group that groups one or more routing tables of the source logical router and the destination logical router to form the RIB group; forming, by the virtual network controller, a unidirectional policy defining one or more rules for controlling leaking of one or more of the routes through the logical router interconnect from the source logical router of the first virtual network to the destination logical router of the second virtual network wherein forming a unidirectional policy comprises defining one or more rules specifying actions for the physical devices to apply, based on a community name or community member associated with the RIB group, to routes leaked via the logical router interconnect; and pushing, by the virtual network controller, the unidirectional policy to the one or more physical devices of the switch fabric for application to communications through the logical router interconnect.