The RBI said it will conduct on-tap long-term repo operations, open market purchases of bonds and special open market operations (S-OMOs), and also provide the increased held-to-maturity limit to banks until March 2022 versus March 2021.

"For the bond market, this is like an early Diwali and just as the March policy (decision) was termed a bazooka, there is enough today to light up some fireworks," said Arvind Chari, head of fixed income and alternatives at Quantum Advisors, referring to the Hindu festival of lights which falls next month.

The benchmark 10-year bond yield dropped as much as 10 basis points to 5.92% on Friday. The measures were announced alongside a monetary policy committee decision.

The MPC kept rates on hold as predicted while keeping policy stance accommodative to help pull the coronavirus-ravaged economy out of its worst slump in four decades.

Bond markets have been stressed in recent months by the government's record 12 trillion rupee ($164.16 billion) borrowing program and higher borrowing requirements by states.

"In order to impart liquidity to state development loans (SDLs) and thereby facilitate efficient pricing, it has been decided to conduct OMOs in SDLs as a special case during the current financial year," RBI Governor Shaktikanta Das said, adding these and other measures should ease fears about illiquidity.

Market participants had complained of a lack of clarity on what measures the RBI would take, amid fears the government could further increase borrowing in the last quarter if revenues remained weak.

"We look forward to cooperative solutions for the borrowing programme for the second half of the year. It is said that it takes at least two views to make a market, but these views can be competitive without being combative," Das said.

Analysts said the measures should help bring down yields across the spectrum in government bonds, state loans and corporate bonds.

"The RBI has never been so explicit in its support to the bond market," Quantum's Chari said.

(Reporting by Swati Bhat; Editing by Euan Rocha and Kim Coghill)

By Swati Bhat