UPDATE 1-GSK CEO says strong interest in OTC products sale

* Witty sees sale process picking up over summer

* Demand from industry rivals and private equity

* GSK looking for more small deals in China

* Emerging market deals difficult due to "sky-high" prices

(Adds details, background)

BRUSSELS, June 14 (Reuters) - Drugmaker GlaxoSmithKline (GSK.L) has seen strong interest from both industry rivals and private equity houses in a clutch of non-prescription products it is looking to sell, its chief executive said on Tuesday.

The sale process for the over-the-counter (OTC) medicines on the block is likely to pick up over the summer, Andrew Witty told reporters during a meeting of pharmaceutical industry executives in Brussels.

British-based GSK is selling several OTC drugs marketed primarily in Europe and the United States with combined sales of around 500 million pounds ($815 million) in order to make its portfolio more focused. The sale includes the diet pill Alli.

Industry analysts believe the auction, which is being conducted by Goldman Sachs, could bring in 1.5 billion to 2 billion pounds.

GSK earlier on Tuesday announced it was buying the remaining 51 percent in a flu vaccine joint venture in China for 24 million pounds, and Witty said he was looking for further small acquisitions in the country. [ID:nLDE75D093]

Overall, however, he said he expected fewer bolt-on acquisitions in emerging markets in future because valuations had gone "sky-high" in the last 12 months. (Reporting by Ben Deighton; additional reporting by Ben Hirschler in London; Editing by Will Waterman) ($1=.6131 Pound)