Official sources said Kataria conveyed to the Prime Minister that since the other Minister of State Jitendra Singh also hailed from Rajasthan like him, he would find it difficult to work there.
However, sources said Kataria's real grouse was that Jitendra Singh was tipped to get charge of defence production, while he would be left with only the subjects of NCC and Ex- Servicemen to look after.
Official sources said the Prime Minister has agreed to look into his request for a change in portfolio.
First-time inductee into the Union Council of Ministers, Kataria was sworn-in along with 21 other union ministers on Sunday.
Meanwhile, Jitendra Singh, who has already assumed charge in the Defence Ministry and as Sports Minister with independent charge, attended the crucial Defence Acquisition Council (DAC).
Thirteen other union ministers also called on the Prime Minister, official sources said.
