From The Hindu

Russia and Iran signed a comprehensive strategic partnership treaty to enhance cooperation in trade, military, science, and culture – amidst growing Western sanctions and geopolitical challenges.
Key Objectives:

Strengthen economic and trade relations, addressing technical obstacles for gas shipments and transport corridors.
Enhance military and technological collaboration, particularly in response to Western sanctions.
Foster regional stability through mutual cooperation, countering external interference (especially the U.S.).
Context and Necessity:

Sanctions: Both Russia and Iran are facing severe Western sanctions, prompting the need for closer ties.
Geopolitical Alignment: Russia and Iran share common interests in countering U.S. influence in the region, particularly in West Asia.
Past Cooperation: Historical ties include nuclear energy projects and mutual support in Syria and Ukraine.
Significance:

The treaty is seen as a strategic move to secure economic and military support amid growing external pressures, especially from the U.S.