At that time, it called itself Marxist-Leninist Centre (Marxistisch-Leninistisch Centrum) and transpired by the Communist Party section 33 in Blijdorp, Rotterdam.

Before the 21st CPN party congress, MLC issued the appeal 'For the Unity of the Communist Movement'.

Plans for a merger stalled, as the Rode Vlag-group maintained that it was still possible to convert CPN into a revolutionary party.

In March 1965, MLC changed its name to Marxist-Leninist Centre of the Netherlands (Marxistisch Leninistisch Centrum Nederland).

In 1966, MLCN launched a youth wing, the Young Communist League, that did not last long.

Other KEN (ml) fronts were the League of Tenants and House-seekers (Bond van Huurders en Woningzoekenden, BHW) and Workers Power (Arbeidersmacht).

The majority led by Monjé supported the line that the working class had to be the supreme force in the revolutionary struggle.

In October a majority of around 60% left to form the Communist Party of the Netherlands (Marxist-Leninist) (KPN (ml)) with Monjé as their leader.

The 'new' KEN (ml) became primarily active in Rotterdam ports, the shipbuilding industry and dockers- and metalworkers unions.

Similarly, a group of KEN (ml) members from the Brabant town of Breda, who refused to move to the Rotterdam area, broke away in August.

One of the issues raised by KEN (ml) in the electoral campaign was a discourse in support of the unity of independent Western European countries against the imperialism of the two Superpowers.