I am planning overlanding trip from EU to Mongolia and want to take my cat with me. He has been traveling with me before but only short term, he likes to be in wilderness and usually I keep him off leash when in nature.

Does anyone have been traveling with their pet? What kind of documents do I need to show on a border? Would it be possible to bring him to China if we countinue our trip?

He has passport and is vaccinated.

Thank you fellow travelers