Adverse conditions may allow certain U.S. citizens to claim foreign earned income and housing cost exclusions [Rev Proc 2009-22]:
Individuals who were forced to leave certain foreign countries in 2008 because of adverse conditions may still qualify as bona fide residents of that country for purposes of the IRC §911 foreign income tax exclusion. Under IRC §911(a), qualified individuals may exclude foreign earned income and housing expenses from their gross income for tax purposes.
To qualify for the exclusion, an individual must prove that he has lived in a foreign country for at least 330 full days during any period of 12 consecutive months. However, if instances of war, civil unrest, or other adverse conditions force an individual to leave a country before the 330-day requirement is met, that individual can still qualify for the exclusion if he can prove that he would have otherwise stayed in the country.