The board of Brazilian state-led oil company Petrobras has delayed approval of a five-year business plan for a second time, which may indicate strain between management and the federal government over the size of the company's investments.

During a meeting, the board urged Petrobras executives to conduct additional 'stress tests' of how the proposed 2011-2015 investment plan might be affected by changes in the economy, the company said in a statement.

The new investment guidelines, which were to have been unveiled two months ago, are being drafted to replace Petrobras' $224 billion, 2010-2014 outlook.

Petrobras' management earlier this year sought approval for a large increase in outlays.

The proposed increases sparked investor concern that the company would have to increase borrowing or sell new stock to finance the increase, sources familiar with the situation said.

But government-appointed members of the board, who control a majority of Petrobras voting stock, told executives to keep spending roughly in line with the current five-year plan.

With average spending of $123 million a day, it is already the world's largest corporate investment programme.

'It should take more than a week to adjust everything,' said a company source, who asked not to be identified, without offering details.

The company's nonvoting shares, its most widely traded class of stock in Brazil, closed 0.2 per cent lower at 23.34 reais on Saturday.-Reuters