Tehran: Tehran has lashed out at the decision by UN's top human rights body to appoint a special investigator to look into allegations of human rights abuses in Iran, saying the newly created post is "politically motivated."

Foreign Ministry spokesman Ramin Mehmanparast said on Friday the appointment came "under US pressure" to divert attention from abuses in the United States.

The UN Human Rights Council on Thursday narrowly approved a US and Swedish-backed proposal for a special rapporteur for Iran.

The decision marks the first time since the Geneva-based council's creation in 2006 that a new position for a country-specific investigator was created. Iran is not a council member.