Vietnam has started commemorations for the 70th anniversary of the Dien Bien Phu battle in which the French colonial army was defeated by Vietnamese troops.

"A lesson from the Dien Bien Phu campaign is that Vietnam must clearly identify its national interests and pursue these interests strategically," Carl Thayer, a senior expert in V

The battle saw the defeat of the French colonial army by Vietnamese troops, a decisive point that ended French colonial rule after almost a century.

A crowd of more than 10,000 people including war veterans and dignitaries gathered Tuesday in Vietnam's Dien Bien Phu to mark the 70th anniversary of the battle that ultimately brought an end to the French empire in Indochina.