How can I get the official letter for visa application?

I have been to the Chinese Embassy here in Qatar and they told me that as part of the new policy for acquiring visa, Filipinos should provide Official Letter from the Chinese government. And that I can ask the inviting party to help me in requesting for it. However, after sending request to them, they informed me that they are not authorized to request on my behalf.
What I have is a printed copy of the invitation letter from the organization that provided me the invitation. And they are just proposing that they send me the original (with seal).
Is there any alternative way that I can get this Official Letter? Or are there other requirement in place of this one?
Hope you can help me with this one.