This is permitted provided that no haram would be done. So for example, a Muslim may not go to a haram environment like a pub or club. Let us say the Muslim even goes to a normal restaurant but then his non-Muslims colleagues consume alcohol; he would not be permitted to sit on the same table as them in which alcohol is being drunk at.
If however they go to a restaurant and there is no drinking alcohol on the same table, and the food is halal, then there is no issue and it is permitted inshallah.
May Allah grant you success