In a first public reference to his uncle's recent execution, North Korean leader Kim Jong-Un has spoken of the "elimination of factionalist filth" .
In a new year message broadcast on state TV, Kim said "resolute action" had strengthened the country's unity, BBC reported Wednesday.
Last month North Korea announced it had executed Chang Song-thaek for "acts of treachery".
The move raised concerns of instability in the secretive nuclear-armed country.