The Reserve Bank of India's benchmark repo rate was raised by 50 basis points on Friday, the fourth straight increase in the current cycle, as policymakers extended their battle to tame stubbornly above-target retail inflation rate.

The monetary policy committee (MPC), comprising of three members from the RBI and three external members, raised the key lending rate or the repo rate to 5.90% with five out of the six voting in favour of the hike.

The RBI has now raised rates by a total 190 basis points since its first unscheduled mid-meeting hike in May but inflation continues to remain stubbornly high - a phenomenon that is affecting much of the global economy.

"The inflation trajectory remains clouded with uncertainties arising from continuing geopolitical tensions and nervous global financial market sentiments," Governor Shaktikanta Das said in his address accompanying the MPC's decision.

"In this backdrop, MPC was of the view that persistence of high inflation, necessitates further calibrated withdrawal of monetary accommodation to restrain broadening of price pressures, anchor inflation expectations and contain the second round effects. This action will support the medium-term growth prospects of our economy," he added.

The U.S. Federal Reserve's relentless and aggressive interest rate hikes over recent months to curb inflation have battered the rupee, and most other emerging and developed market currencies.

Policymakers around the world are grappling with a sweeping shift away from their respective currencies and into the safe-haven dollar, raising worries of capital outflows and further damage to their economies.

Economists say the RBI too would need to focus on ensuring the interest rate differential is not too low. [

The standing deposit facility rate and the marginal standing facility rate were also increased by the same quantum to 5.65% and 6.15%, respectively.

India's annual retail inflation rate accelerated to 7% in August, driven by a surge in food prices, and has stayed above the RBI's mandated 2-6% target band for eight consecutive months.

The benchmark 10-year bond yield eased marginally after the RBI's decision to 7.3737% at 0440 GMT while the partially convertible rupee weakened to 81.63 per dollar, from 81.57 prior to the policy decision.

The NSE Nifty 50 index was down 0.10% at 16,801.85, and the S&P BSE Sensex fell 0.07% to 56,373.19. (Reporting by Swati Bhat; Additional reporting Nupur Anand; Editing by Shri Navaratnam)