hi ani,

http://www.britainincanada.org/Visa/transit.htm" target="_blank">http://www.britainincanada.org/Visa/transit.htm</a>

check this

\"a valid airline ticket for travel via the United Kingdom as part of a journey from Australia, Canada, New Zealand or the United States of America to another country or territory, provided that the transit passenger does not seek to transit the United Kingdom on a date more than six months from the date on which he last entered Australia, Canada, New Zealand or the United States of America with a valid visa for entry to that country\"

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Sukhwinder Singh