"Sidbi's `AAA' rating factors the strong capital adequacy position and its strong resource raising capabilities due to government support, both of which contribute to its profitability performance," a rating agency release on Wednesday said. "The key sensitivities are the emerging pressures on the Sidbi's asset quality since it has a significant exposure to the state finance corporations (SFCs) and state industrial development corporations (SIDCs)," Crisil added.

The asset quality of the SFC/SIDC exposures taken by Sidbi is influenced by the weak financial performance of theseinstitutions, high level of non-performing assets (NPAs) and the diminishing financial flexibility of these entities. "The reluctance to recapitalise the SFCs and the absence of any asset quality protection to Sidbi's refinance portfolio further accentuate the asset quality risks," Crisil said.

The `AAA' rating to the outstanding bonds of IRFC reflects the level of integration of IRFC with the Indian Railways (IR) and its strategic importance as the only agency through which IRFC borrows funds from the market, the rating agency release said.

"IRFC has demonstrated the ability to raise long term resources and has improved its asset liability management profile over the past years. The institution currently borrows long tenor funds on amortising payment structures to match its lease rental receivables," Crisil said, adding that the annual lease agreements between IRFC and the IR provide a comfortable spread to IRFC and pass on the foreign exchange and interest rate risks to the Indian Railways.

Crisil haswithdrawn the `A+' rating assigned to the Rs 10.5 crore NCD portion of the partly convertible debenture programme of CHL since the company has made arrangements for redeeming the debentures by transferring the amount payable on the outstanding debentures to a seperate account on the due date.

Meanwhile, another rating agency, Icra, has reaffirmed the `A1+' highest safety rating to the Rs 100 crore commercial paper (CP) programme of Wipro Ltd.

"The rating factors in the strong cash accruals generated mainly from Wipro's software business, favourable industry outlook for the software industry and the reduction in gearing following pre-payment of most of its term liabilities and strong liquidity," an Icra release said.