All perfect praise be to Allah, The Lord of The Worlds, and may His peace and blessings be upon our Prophet Mohammad and upon all his family and companions.
Moving Zakat (Obligatory charity), including Zakat-ul-Fitr, to a country other than the one in which it is due is permissible so long as there are eligible recipients in that country; particularly if need arises for doing so. For example, there are poor relatives, there are people in dire need or a catastrophe has taken place, and the like. The proof of this is the Hadith reported on the authority of Ta`woos, and in which Mo`ad said regarding Zakat, to the people of Yemen: "Give me clothes as Zakat instead of barley and corn, for this is easier for you and better for the Companions in Medina." {Related by Bukhari}. This shows the permissibility of moving Zakat from Yemen to Medina.
This is the view of the early and late scholars from the Shafie school of thought. Al-Qhaliobi said: "The second opinion: Moving Zakat to another country is permissible and avails the giver " {Al-Hashiyah Ala Shareh Al-Minhaj}. As for the evidence adopted by the scholars who forbade moving Zakat to another country, it is the Hadith: "………it (Zakat) is to be taken from the wealthy among them and given to the poor." In his commentary, Daqeeq Al-Eid said: "It is weak Hadith since the evident meaning is that Zakat is to be taken from the wealthy as Muslims, not as people of Yemen. In addition, it is to be given to the poor as Muslims as well. Although this view isn`t the most apparent; it is highly likely." {Ehkam Al-EhkamSharehUmdat Al-Ahkam}.
As for Zakat-ul-Fitr, it should be estimated according to the country where one lives, and not according to where he comes from.
Al-Imam An-Nawawi said: "If he had some of his wealth with him in a certain country and another some was in a different country, then Zakat-ul-Fitr is due in the country where he is, and there is no disagreement amongst the scholar on this.(1)" And Allah knows best. (1): added 21/7/2014.