The 'Northern Union', as it was also called, was one of the principal roots of the unified Socialist-Revolutionary Party (PSR) that emerged.

To protect Azev's cover, the police allowed Argunov to continue his revolutionary activity unmolested until Azef left Russia in November 1901.

The unified PSR adopted a compromise position, endorsing terrorism and organisational work among workers, peasants and intellectuals alike.

At that time, in 1909, Argunov was living in Paris, but was dispatched by the Central Committee to St Petersburg to interview A.A.Lopukhin, the Okhrana officer who wanted the police to stop using Azef as a double agent, and reluctantly accepted the truth.

He edited the war time social patriotic journals За рубежом and Новости.

Returning to Russia in 1917, he supported the government of Alexander Kerensky, and edited the pro-Kerensky journal Воля Народа.