The national broadband network jigsaw puzzle appears to be finally forming as another piece has been added to complete the picture with independent Senator Steve Fielding providing maybe the final link, announcing on late Wednesday that he would support the NBN bill.

Along with the vote of another independent Senator Nick Xenophon, the federal government seemed to have mustered enough numbers that would sufficiently push its NBN legislation poised to divide Telstra Corporation's wholesale and retail arm, which it said would be material to the successful implementation of the broadband project.

Prime Minister Julia Gillard won the backing of the independent senators by agreeing to release a summary of the NBN business plan, which lawmakers have been demanding to see prior to the Parliament's rise for a long summer break.

Ms Gillard also assured Senator Xenophon that a joint committee of the parliament would be given the responsibility to oversee the full roll out of the NBN, thereby strengthening the favourable position that the project now enjoys with most of the lawmakers.

Yet even as the government now brandishes the required numbers to see through the realisation of the NBN project and the partitioning of giant telco firm Telstra, the opposition remains adamant and vowed to devise ways in delaying the project's anticipated approval when MPs and senators hold their final session this week before heading for a long break.

The released NBN brief, according to Ms Gillard, is now carrying a much lighter financial cost of $37.5 billion for its actual implementation, largely detracting from the previous guidance cost of up to $43 billion and further proving the project's financial viability.

She added that the released summary has been freed from any information that the federal government deems would only create undue market jitters.

However, the opposition decried the document's incomplete contents as opposition communications spokesman Malcolm Turnbull scored Ms Gillard for deliberately holding back on pertinent information on the NBN business plan such as its balance sheet and cash flow declarations.

Turnbull insisted that despite Ms Gillard's effort to give considerable grounds on opposition demands on NBN, his call for a Productivity Commission inquiry on the project remains.

Ms Gillard expressed no surprise on the continued displeasure of the opposition notwithstanding the initiatives pushed forward by the Labor-led government as she stressed that "there's no point in them wasting their time reading because they won't care what it says."