It is claimed Wales is losing lottery funding to pay for the London games
A Welsh MP has echoed the concerns of a former UK Sports minister casting doubt on the long term benefit of the London Olympics to the rest of the country.
Labour MP for Vauxhall Kate Hoey told the London Evening Standard she had "no idea" what was happening regarding the promised 2012 legacy beyond London.
Plaid Cymru MP Hywel Williams said Wales was losing out on £437m funding.
But a UK government spokesperson said Wales was realising sporting, economic and cultural opportunities.
Ms Hoey, who was UK sports minister from 1999 to 2001, is reported to have said that there's been "a government failure" regarding the legacy of the games for the entire country.
Kate Hoey was UK sports minister from 1999 to 2001
She told the newspaper: "The rest of the country was also promised legacy and I have no idea what is happening... unless things change I fear a backlash."
Mr Williams, MP for Caernarfon, said Wales was losing out on around £437m of Olympic funding and that "we will have little or nothing to show for it instead".
Last year a report by MPs on the Welsh Affairs Select Committee estimated Wales could lose around £100m in lottery funding to pay for the London games.
The London Olympics are considered as 'UK spending' in government funding terms, so don't trigger the so-called 'consequential' additional Welsh funding that they would if classified as spending for England alone.
Plaid Cymru argue that Wales is missing out on around £330m as a result.
Mr Williams said: "In my constituency in north west Wales the positive impact of the Olympics will be limited, if not non-existent.
"However, the London Olympics will be based almost exclusively in the south-east of England, less than a handful of business contracts have been given to Welsh firms, London politicians have admitted that it is a scam to use public money to regenerate one of Europe's richest cities and those currently in the Labour UK Government refuse to admit that Wales will lose out."
Benefits to Wales
A Department for Culture, Media and Sport (DCMS) spokeswoman said Welsh businesses were winning both direct and supply-chain Olympic contracts.
She said Welsh companies were providing the steel frame for the Aquatics Centre and the steel reinforcement system for the Olympic Stadium.
The spokeswoman added that 32 venues in Wales had been identified as potential pre-games training camp venues, the Australian National Paralympic committee had signed an agreement to hold camps in Wales and the Millennium Stadium would host rounds of the football competition.
She added: "Wales will have four major projects funded by a £1.67m grant from the Legacy Trust, under the title: The Power of the Flame.
"This will offer young people opportunities for personal development through artistic and sporting events and there will be live sites in Cardiff and Swansea where people can watch the games and join the celebrations in 2012."
A spokesperson for the Sports Council for Wales said "It is essential that we maximise on the potential and use the lead up to the games to provide opportunities in a wide range of sports and to help unite a proud sporting nation here in Wales."