The two parties took ITV to the High Court, saying their exclusion deprived voters of the chance to make their own decisions.
The Liberal Democrats and the SNP have lost an appeal to be included in a leaders’ debate on ITV tomorrow.
Boris Johnson and Jeremy Corbyn will now go head-to-head without Jo Swinson and Nicola Sturgeon, as planned.
The judges concluded: “No arguable breach of the broadcast code is shown.”
They said the format of the debates was a matter of “editorial judgment”.
They also refused permission for the two parties to appeal the decision.