The NKNews website, which monitors developments in the secretive state, reported that the austere images were taken down earlier this year, but have never been replaced.
Lenin and Marx had glared out over the square, used for military march-pasts and mass rallies in support of the regime for decades, despite the Workers' Party of Korea revising its charter in 1980 to replace their concepts with those of Kim Il-sung.
NKNews said there are no indications as to why Marx and Lenin are being air-brushed out of North Korean history at this time.
According to the Telegraph, Kim Jong-un, the 29-year-old leader of the nation, is reportedly behind efforts to improve the lives of ordinary people and has made careful moves to shift control away from the all-powerful military.
Analysts believe that he is also trying to win the support of the public by making himself more accessible and visible in everyday life.
Since he assumed power in December last year, he has publicly chastised the operators of a shabby theme park, staged a television show with Disney characters and married an attractive pop singer, the report said.
He is also likely to have been behind the decision to replace another portrait in Kim Il-sung Square, of his grandfather wearing a fierce scowl, with one of a smiling and more benevolent-looking picture of the founder of the nation, the report added.
London: Portraits of founding fathers of communism, Lenin and Karl Marx, which once dominated Kim Il-sung Square in North Korea, have now been removed.
First Published: Monday, October 15, 2012, 20:01