As life expectancies worldwide keep rising, countries around the globe may want to consider lifting the retirement age so they can continue to pay for national pension plans, the Organization for Economic Cooperation and Development said in a report.

Life expectancy at birth is expected to rise by more than seven years in developed economies over the next 50 years, the OECD says. The long-term retirement age in half of all OECD countries will be 65, while in 14 countries it is expected to range from 67 to 69. Increases in retirement ages are under way or planned in 28 of the 34 OECD countries, says the group's Pensions Outlook 2012, published on June 11.

"Breaking down the barriers that stop older people from working beyond traditional retirement ages will be a necessity to ensure that our children and grandchildren can enjoy an adequate pension at the end of their working life," said OECD Secretary-General Angel Gurría in a statement. "Though these reforms can sometimes be unpopular and painful, at this time of tight public finances and limited scope for fiscal and monetary policy, these reforms can also serve to boost much needed growth in aging economies."