American Express (NYSE:AXP) is in no rush to offer a crypto-linked card, CEO Stephen Squeri said at Yahoo Finance's All Markets Summit. "You are probably not going to see an AmEx crypto-linked card anytime soon," Squeri said. Instead, he prefers to take a more disciplined approach to cryptocurrencies. He said he views the major cryptocurrencies like an asset class such as gold. "I don't see it as really something that's going to make inroads with a credit card perspective in terms of payments," he said, citing two reasons — cryptos' volatility and the service AmEx (AXP) would have to provide. AXP shares edge up 0.1% in after-hours trading. Earlier on Monday, Bakkt forms a partnership with Mastercard that's intended to make it easier for consumers to pay using crypto.