Gap non-executive chairman Robert Fisher will serve as president and chief executive officer on an interim basis.
Pressler has headed the US retailer since 2002. He said: 'I have enjoyed the opportunity to lead this iconic company over the past four years. It has been a pleasure to work with the management team and such talented people throughout the organisation.'
Fisher said: 'We want to thank Paul for all the hard work and dedication he has shown over the past four years. Under his leadership, the company has meaningfully improved its operations, strengthened its balance sheet and greatly enhanced its online presence across the brand portfolio.
'I look forward to serving our employees, customers and shareholders as interim chief executive officer.'
Gap revealed net sales were down 4 per cent to US$2.34 billion (£1.18 billion) for the five weeks ending December 30, cutting its full-year profit forecast.
The company's comparable store sales decreased 8 per cent; with Gap North America down 9 per cent, Banana Republic up 2 per cent, Old Navy North America decreasing 10 per cent and International sliding 8 per cent.
The company said that it expects the percentage increase in sales per sq ft to be in low single-digits by the end of the fourth quarter of the current financial year.
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