During a project dinner (e.g., Steering Committee meeting), can the entire restaurant bill be declared if it includes the share of a partner whose costs are already covered under the Travel and Accommodation budget?

Yes, it is possible for a partner to organize a meal for all participants in their city and declare the expense, even if they do not claim Travel & Accommodation costs for that occasion. In this case, the expense can be considered a collective cost related to the organization of an event.