Grocery sales led the way as Scotland's retailers saw their return to growth continue in August, analysis shows.

Total food sales last month rose by 4.1% compared to the same period last year, taking the 12-month average growth (at 2.3%) to its highest level since June 2014.

In August, Scottish sales increased by 1.9% on a like-for-like basis, which excludes new store openings, compared to August 2016.

Total sales rose by 1% when set against the same month last year, according to the latest Scottish Retail Consortium (SRC)-KPMG Scottish Retail Sales Monitor.

Adjusted for deflation, measured at 0.3%, overall August sales grew by 1.3%.

Total non-food sales declined by 1.5% compared to August last year, the monitor found.

But when the figure was adjusted for the effect of online sales, non-food sales were actually found to have risen by 0.9% over the same period.

Experts warned that underlying challenges continue to face the industry, including the pressures on household incomes.

Craig Cavin, head of retail in Scotland at KPMG, said: "Scottish retail's return to growth continued in August, as food sales' sustained period in the black was extended.

"Grocery sales lead the charge once again, with a 4.1% year on year increase bringing the 12-month average to its highest level for more than three years.

"With August bringing children's return to school, the Edinburgh Festival and the release of autumn clothing ranges, non-food's recent poor performance received a late summer boost, with online sales nudging the category into growth."

He added: "However, despite home furnishings, TVs and fridges all selling well as consumers prepare their houses for the longer autumnal evenings, other non-food remained in decline.

"Looking ahead, shop owners will have one eye on the Scottish Government's taxation plans, announced in the coming weeks, as they look for greater support for the industry."

Ewan MacDonald-Russell, the SRC's head of policy and external affairs, said: "It's important to note both food and non-food are being compared to a very poor August in 2016.

"Therefore, the apparent spike in performance may well be a statistical quirk rather than evidence of sustained sales improvement.

"Nonetheless retailers will welcome these figures after a pretty disappointing summer."