TAIPEI—Taiwan Foreign Minister Joseph Wu urged “freedom-loving countries” on Friday to work together against China, during a rare trip to Europe taking place amid heightened tensions between Taipei and Beijing. Self-ruled Taiwan, which China claims as its own and has not ruled out taking by force, does not have formal diplomatic relations with any European countries apart from Vatican City. But it is keen to deepen ties with the European Union democracies. Wu’s European trip has angered Beijing, which last week warned Slovakia and the Czech Republic against undermining their bilateral relations with China by allowing Taiwan to visit those countries. “The rise of the People’s Republic of China, as led by the Chinese Communist Party, is the defining challenge for the world’s democratic states. This warrants our working more closely together,” Wu said in a virtual address at a summit held in Rome by the Inter-Parliamentary Alliance on China, …