London: Treasurer Josh Frydenberg has ruled out delaying the budget surplus even if the economy continues to weaken.

On Friday, the NAB declared Australia's retail sector already in recession and some economists fear the entire economy could next year fall into recession, ending the country's much-vaunted 28-years of economic growth.

"No", was Treasurer Josh Frydenberg's unequivocal response when asked in London if he would consider pushing back the budget surplus. Credit:AAP

Mr Frydenberg told a business audience in London that the biggest threat to Australia's economic conditions remained US-China trade tensions.

"From Australia's perspective, we call for cool heads to prevail," Mr Frydenberg told the Australia-United Kingdom Chamber of Commerce at Macquarie Bank's headquarters in the Square Mile.