Mr O'Brien all but declared "mission accomplished" on Friday in his three year shake-up of the group's flagship supermarkets division where it could now confidently stare down upstart rival Coles while also fending off new entrants such as German discounter Aldi and US player Costco.

But while Woolworths was busy behind the scenes investing millions into Big W to transform the entire business and scurrying to drag Masters  out of the red, Australia's economic framework was still too fragile to support robust consumer expenditure.

"The last six weeks for us has been steady," Mr O'Brien said.

"For us July and August haven't varied that much, any sort of customer confidence [measure] you look at they are not at the most confident at the moment and I think it's important to call that out and, from our perspective, that's why we view customers will remain cautious which means we need to work harder to earn their custom."

Mr O'Brien added that such was the uncertainty in the economy that trading conditions remained challenging with households managing costs of living pressures.

This could force Woolworths to potentially dump its tradition of providing profit guidance at its full-year results, with this year's projection of net profit rising 4 per cent to 7 per cent in fiscal 2015 potentially the last time it would deliver an earnings forecast to the market.

Woolworths yesterday posted an 8.5 per cent rise in net profit to $2.45 billion while normalised profit that strips out one-offs lifted 6.1 per cent.

Earnings per share was 5.3 per cent higher to $3.775 billion.

Sales of $60.8 billion was 3.9 per cent better, or 5.9 per cent on a normalised 52-week basis.

The supermarkets did the heavy lifting, particularly fresh food and liquor, driven by improving margins and greater market share.

Food and liquor sales from its core Australian supermarkets increased 4.9 per cent to $48.23 billion as pre-tax earnings were up 5.3 per cent at $3.368 billion.

Gross margins rose to 25.19 per cent from 25.1, while the cost of doing business eased by 6 basis points.

This made up for a 20.1 per cent slide in earnings for Big W to $152.9 million and a $169 million loss for its home improvement division which is dominated by Masters and signalled to the market this month.

Mr O'Brien said much of the hard work had been done at Woolworths supermarkets, meeting strategic goals he set in November 2011 when only one month in the role he pledged to investors to return the days when Woolworths could brag double-digit profit growth.

He said the priority of the last few years was food and liquor and although there was always work to do there, it was now time to grapple with other businesses under the Woolworths shingle.

"We are also investing in the future, we called out three years ago Big W needed to be a different business for the future and we chose this financial year we are reporting on today to start those changes proactively and we are building a new business in Masters."

He said his ambition, unveiled in 2011, to hit high single-digit sales growth as well as 10 per cent earnings per share growth was still achievable.

Woolworths declared a final dividend of 72 cents per share, up 1 cent, payable October 10 to take the full year pay-out to $1.37 per share.