Ethics of a journal requiring that submissions cite existing articles in the journal Recently, I became aware by own experiences and friend's stories that some international statistical journals (whose names I prefer to omit) are rejecting papers because they do not include a reference of the journal in question. This is, if you do not cite a paper from journal X, then you cannot attempt to publish a paper in journal X. 

This, of course, has an influence on the Impact Factor of the journal and the administrators are trying to increase this.

Are there explicit regulations regarding these issues? Is it possible to denounce this kind of behaviour?
There are no explicit regulations regarding impact factors; the definition is too simple. (In terms of complexity, it's a lot like calculating a slugging average in baseball. So it's open to a lot of manipulation, and all of it is permissible. However, permissible does not mean ethical, and this is clearly a situation where, if true, the journal editors are trying to manipulate statistics to make their journal look better. Such a policy, if done with the intent of manipulating statistics, is deplorable, and should be denounced—via web campaigns, blog posts, open letters, and so on.

That said, there is a counterargument that is less nefarious in aim. It is possible to argue that you should, in general, cite some article from the journal you're submitting a paper to. If you can't do that, why is your article suitable for submission to that journal (let's call it journal X)? Presumably, there are a number of other journals (A, B, C, etc.) whose works you have cited instead of X. In that case, the journal could argue that your paper is a better fit for journals A, B, and C instead.

Since it's not clear for which reason the journal has the self-citing policy, I would make sure that you can determine it convincingly, one way or the other, to avoid embarrassing yourself. The last thing you want to do is spearhead a campaign that turns a molehill into a mountain.