ABUJA (Reuters) - Nigerian Senate committee members want additional time to finalise controversial legislation that would overhaul Africa's biggest oil and gas sector, a senior lawmaker said on Monday.

The OPEC member wants to drastically change its oil sector with legislation to restructure state-run Nigerian National Petroleum Corporation (NNPC) into a profit-driven firm like those in Brazil, Malaysia and Saudi Arabia.

But foreign oil companies in Nigeria have warned the plans contained in the Petroleum Industry Bill could threaten billions of dollars of investment if they go ahead in their current form.

A joint Senate committee was expected to send a final version of the nearly 1,000-page bill to the full Senate earlier this month, but lawmakers said they needed more time.

"The joint committee will certainly request the Senate for an extension of time. At least two weeks to tidy it up and submit the report," a senior senator told Reuters.

"The main issues are the fiscal regimes, like taxes and such," said the senator, who asked not to be named.

The far-reaching bill, which has been in planning in some form for more than a decade, has been promoted by the presidency as the answer to problems including funding shortfalls, domestic gas shortages and budget-debilitating fuel subsidies.

In its present draft, the legislation could allow the government to renegotiate old contracts, impose higher costs on oil companies and retake acreage that firms have yet to explore.

The bill could also contain a provision, supported by President Umaru Yar'Adua, to provide 10 percent of Nigeria's oil joint ventures to the Niger Delta. The plan could translate into hundreds of millions of dollars each year in cash benefits for impoverished residents in the oil-producing region.

It is not clear whether Yar'Adua will get enough political support from non-oil states, which represent the vast majority of Nigeria, to pass the bill through parliament.