To help encash the bonds issued to the central power public sector undertakings, the Reserve Bank on Tuesday permitted trading in some of these papers maturing in 2013-14.

The bonds were issued to these public sector undertakings as many state electricity boards had failed to pay back their dues.

"RBI has permitted trading in and transfer of power bonds maturing on October 1, 2013 and April 1, 2014," the central bank said.

As part of one-time settlement of the dues owed by state electricity boards to PSUs like National Thermal Power [Get Quote] Corporation, NHPC, Power Grid Corporation of India Limited and coal PSUs, an agreement was reached between 27 state governments, Union ministry of power and RBI in 2003 to release these bonds for the state-owned firms.

These bonds were envisaged for trading in a phased manner. Already, 10 bonds of various maturities between 2008 and 2013 have been made tradeable.