Not true. Obama's own website stated he is not a natural born citizen but a dual citizen because of his dads british nationality passed to young Barak at birth.
From this website:
Fight the Smears: The Truth About Barack?s Birth Certificate
The relevant Obama admission
At the official Obama campaign website – Fightthesmears.com – just below the Certification of Live Birth (COLB) – the following admission was also published:
When Barack Obama Jr. was born on Aug. 4,1961, in Honolulu, Kenya was a British colony, still part of the United Kingdom's dwindling empire. As a Kenyan native, Barack Obama Sr. was a British subject whose citizenship status was governed by The British Nationality Act of 1948. That same act governed the status of Obama Sr.'s children.
This was republished from a Factcheck.org, article which further stated:
In other words, at the time of his birth, Barack Obama Jr. was both a U.S. citizen (by virtue of being born in Hawaii) and a citizen of the United Kingdom and Colonies (or the UKC) by virtue of being born to a father who was a citizen of the UKC.
You cant argue with that. Futher the U.S. State Department's Foreign Affairs Manual discusses problems associated with dual citizenship:
7 FAM 081: U.S. Policy on Dual Nationality:
(e)While recognizing the existence of dual nationality, the U.S. Government does not encourage it as a matter of policy because of the problems it may cause. Dual nationality may hamper efforts by the U.S. Government to provide diplomatic and consular protection to individuals overseas. When a U.S. citizen is in the other country of their dual nationality, that country has a predominant claim on the person.