Soaring demand for Johnnie Walker whisky and a resurgence in Guinness yesterday helped drinks giant Diageo post a 7% sales increase and confidently predict it is on track for a 9% annual organic operating profit growth for the year.

Diageo's prime brands, Johnnie Walker whisky, Smirnoff vodka and Captain Morgan rum, all delivered double-digit net sales growth for the company in the six months to December 31, while Guinness, which had been struggling, saw sales up 6%. The black stuff even returned to growth in the ailing British and Irish markets.

Investors responded positively, sending Diageo shares up 4.55% to close at 1081p, a rise of 47p.

In all, Scotch whisky helped deliver 33% of the company's net sales growth and was particularly important in helping drive sales in emerging markets.

In its international division, which covers many emerging markets and posted organic net sales growth of 16%, brands such as Buchanan's, Bell's, Old Parr and Johnnie Walker Black Label comprised nearly half of sales.

Sales of Buchanan's soared 14% in Venezuela and Mexico, in part due to price rises.

This fed through to sales among Hispanics in the United States, where Buchanan's sales were up 31%. Overall, Scotch whisky net sales increased 18% in North America.

Johnnie Walker sales grew 16% in the international division fuelled by Mexico and the Middle East. Johnnie Walker also led the way among the newly affluent Chinese middle class, and overall in the Asia Pacific region Scotch whisky sales were up 50%. Bell's did well in South Africa.

In Europe, Scotch sales rose 55% over the same period in 2006. Whisky also comprised some 15% of Diageo's business in Africa and delivered a quarter of the company's growth in the region.

In all, Scotch whisky comprised a quarter of Diageo's global sales.

Its chief executive Paul Walsh, recently appointed chairman of the Scotch Whisky Association trade group, said: "We are the leader in a category that is enjoying a renaissance."

One of the surprises at Diageo was a resurgence in sales of Guinness which gained 6% worldwide. Such had been its lacklustre performance in recent years there had been rumours that Diageo would seek to sell the brand.

However, a poor summer in the United Kingdom, which stayed the usual switch to cider and lager, combined with a boost in marketing, sent UK sales up 3%.

This was its first positive sales performance in the UK since 2005 and it was achieved in a beer market which declined 5% overall.

Diageo also succeeded in driving sales of Guinness in Africa, outside its core market of Nigeria. African sales of the Irish stout were up 13%, helped by branding exercises such as sponsorship of the African Nations Cup in Ghana.

But Diageo faced some headwinds that could still drag on its performance in the second half of its financial year.

It lost its import licence for Korea in the summer and is now required to go via a distributor. It does not yet know if a new import licence application submitted on December 26 will be approved.

It has also been hit by disruptions to the transfer of some of India's busiest airport duty free shops from state ownership. This has resulted in a halving of sales of Johnnie Walker.

These events combined to reduce organic net sales growth in the Asia Pacific region to just 1%.

But Walsh is confident the company is well positioned for any global economic downturn. "I do not think we are immune but you have to recognise we sell affordable indulgences. It is not like buying a new car."

He also cast doubt on the impact of the credit crunch on people who have never heard of monoline insurers.

"For an awful number of consumers life goes on as normal," he said.