* Casino repeats pledge to boost profitability in France * French sales slide compared with surge a year ago * Latin America sales climb 4% in the quarter (Adds details from CFO call with analysts) PARIS, May 6 (Reuters) - French retailer Casino said on Thursday it was considering a stock market listing among the options for its GreenYellow renewable energy subsidiary as it seeks to cut debt. Revenue growth slowed sharply in the first quarter, with a 6.4% fall in sales on a same-store basis in Casino’s core French market, compared to a year ago when sales had surged in the first wave of coronavirus lockdown restrictions. Casino repeated its pledge to boost profitability and cash flow this year in France, which showed greater profitability in the first quarter with the help of cost savings. To boost profitability Casino is banking on monetising client data, making savings from purchasing deals and putting a greater focus on e-commerce, organic food, convenience stores and energy services. Casino, which has been selling assets to reduce its debt, said last month it had launched preparatory work for potential capital increases for its Cdiscount e-commerce and GreenYellow renewable energy subsidiaries. “A listing is among the options for GreenYellow,” Finance Chief David Lubek told reporters. Casino, which controls Brazil’s Grupo Pao de Acucar , posted first-quarter sales of 7.146 billion euros ($8.61 billion). On a same-store basis and excluding acquisitions, currency effects and revenue on fuel, sales rose 0.1% compared to 8.1% growth in the fourth quarter of 2020. In France alone, sales at the Monoprix and Franprix stores, which are located in city centres, were down in the quarter by 3.2% and 9.1%, respectively. Casino said there were fewer tourists in Paris and more Parisians left for other regions due to coronavirus restrictions in the capital and surrounding areas. Sales at the Geant Casino hypermarkets fell 9.7% year on year, reflecting the impact of curfew measures and the drop in traffic due to the closure of shopping centre due to COVID-19 restrictions. The food e-commerce business remained strong, with a 38% jump in sales during the quarter. $1 = 0.8298 euros Reporting by Dominique Vidalon; Editing by Benoit Van Overstraeten and Edmund Blair Our Standards: The Thomson Reuters Trust Principles.