Nigeria has the political support for creating a sovereign wealth fund, but it will take time to finalise details for its financing, the finance minister said on Tuesday.

President Goodluck Jonathan's administration has pushed the idea of a sovereign fund to help Africa's most populous nation save some of its oil revenues for the future, invest in critical infrastructure and help stabilise the OPEC member's finances when world oil prices are volatile. But state governors voiced their opposition last month to using the country's oil wealth as capital for the proposed fund. "There is common consensus that we need to do it," Finance Minister Olusegun Aganga told reporters on the sidelines of an economic summit. "But it will take some time because we need to think properly about the sources of the initial funding," he added without giving a timeline.

The president had wanted his economic team to establish the framework for the fund by the end of July. Aganga said he still wants the fund to replace the country's excess crude account (ECA), a pillar of IMF-backed reforms launched in 2003 into which Nigeria currently saves any oil revenue above a benchmark oil price. Critics of the ECA say there is no clear legal basis on which to determine how the windfall oil savings in the account should be shared between the tiers of government -- federal, state and local -- leading to constant political wrangling and the squandering of much of the money. ‘

(The ECA) has been used for different things in the last few years, which is why we are trying to move away from that and set up a stronger vehicle that is institutionalized," Aganga said. The ECA has around $3.4 billion, less than a quarter of the amount it contained at the start of the current presidential term three years ago. Sceptics say a Nigerian sovereign wealth fund is likely to suffer the same fate as the ECA, with squabbling over who controls the funds and how they are managed