I guess you kinda know the deal because you mentioned your mandarin level already. Basically, if you want to have a proper internship you need to speak English and Mandarin. There are literally thousands of Chinese economics students graduating every year, many of whom can speak English and Mandarin. And as Bency pointed out, not just western economies are having trouble right now. I'm sure you know this though, being an economics student and all.
Personally I do have the same ambition as you though, so I hope you'll find a way. As for myself, I'm taking classes here in the Netherlands and work for the Chinese Student Association, and hopefully I'll be able to go there in my master. I hope you don't mind me asking but are you a bachelor or master student? If you're a bachelor I'd say the chances are very slim. Besides, if you're still in your bachelor try to get some mandarin skills in the UK first.
Anyway, good luck with getting an internship, I hope you'll succeed. If not, don't worry about it for too long and concentrate on the next opportunity. If you want to I can provide you with some internet sites that help you to deal with this kind of stuff, just send me a PM and I'll explain more there.