New Delhi, Dec 26 (IANS): Reacting to the central government's decision to appoint a commission to probe the alleged snooping on a young woman by Gujarat Police, BJP president Rajnath Singh said Thursday it was a step to "tarnish the image of Gujarat government".

"The centre's decision to institute a fresh commission of inquiry into the alleged snooping case is an attempt to tarnish the image of Gujarat government," Singh said.

He added: "It is a step against the federal structure of our constitution. When the state government had already ordered a probe into the case, then what was the point behind setting up a new commission of inquiry?"

Rajnath Singh made the comments in a statement issued to the press.

Leader of Opposition in the Rajya Sabha Arun Jaitley said the decision can be challenged in court.

"The Gujarat government has already set up a commission of inquiry to inquire into this issue. The setting up of a parallel commission by the central government ostensibly on the pretext of this issue covering more than one state is without any basis... I am sure it will be legally challenged in courts," he said.

"It is an affront to the states. I hope other chief ministers also join in the protest against this action," he said.

Jaitley added that the action was "politically motivated".

BJP spokesperson Nirmala Sitharaman earlier said: "The Congress is trying to hit at the principal opposition party's prime ministerial candidate. It is a clear case of political vindictiveness."

The cabinet Thursday ordered a commission of inquiry into the alleged snooping on a young woman by Gujarat Police, allegedly at the behest of then state home minister Amit Shah, informed sources said.

They said the decision was taken at a cabinet meeting presided over by Prime Minister Manmohan Singh.

Two news portals claimed last month that Shah ordered the illegal surveillance of a woman at the behest of a "saheb", widely believed to be Gujarat Chief Minister Narendra Modi.