What's the reason that makes you say so?
"Brit-Am, sometimes confused with
British Israelism, is an organization centered in Jerusalem, and
comprised of Jews and non-Jews. Brit-Am, like British Israel,
identifies the Lost Ten Tribes with peoples of West European
descent, but does so from a Jewish perspective quoting both
Biblical and Rabbinical sources. The evidence that Brit-Am relies
upon is Biblical in the light of Rabbinical Commentary supplemented
by secular studies.
It also believes that "Other Israelite Tribes gave rise to
elements within Finland, Switzerland, Sweden, Norway, Ireland,
Wales, France, Holland, and Belgium" and that "The Tribe of Dan is
to be found amongst part of the Danish, Irish, and Welsh." It
argues that the British Royal Family is descended from the House of
David.None of these ideas are supported by mainstream historians,
archaeologists or genealogists."