PARIS, Jan 18 (Reuters) - French supermarket group Carrefour’s shares slid by nearly 6% on Monday after a possible takeover by Canadian rival Alimentation Couche-Tard unravelled over the weekend. Couche-Tard dropped its 16.2 billion euro ($19.6 billion) bid for Carrefour after the French government opposed the deal, citing food security concerns, though the two companies said they would continue to work on partnership opportunities. Carrefour shares were down 5.8% in early trading, the worst performer on the SBF-120 index in Paris. Analysts at investment bank Citi said there was still a chance that Carrefour and Couche-Tard could revive talks at a later date while the possibility remains for Carrefour and domestic rival Casino to examine a merger deal. “That said, the language and actions of Carrefour and Alimentation Couche-Tard suggest to us the parties would re-engage given even the slightest encouragement, whether now or in the medium term,” Citi analysts wrote. “Moreover, we continue to wonder whether the dalliance with Alimentation Couche-Tard might lead Carrefour and Casino Groupe to reconsider a merger as an alternative, driving both domestic and Latam synergies.” ($1 = 0.8286 euros)