Momentum for Nike Inc.'s North American sales growth, which has faltered in recent quarters, should continue into fiscal 2019, the company's CFO told analysts during a June 28 conference call.

Nike sees its North American sales as a mid-single-digit growth market over the next five years, said Andrew Campion, CFO and executive vice president. The company posted revenue growth of 3% in the region in its fiscal fourth quarter ended May 31, a departure from the 6% decline in the previous quarter.

North American sales helped the athletic footwear and apparel maker beat analyst expectations and year-over-year comparisons for its final quarter of fiscal 2018.

"We have momentum going into the year," Campion said. "We've returned North America to a healthy pull market."

For fiscal 2019, Nike expects high single-digit revenue growth, up from its previous forecast of mid-to-high single-digit revenue growth. The new outlook "takes into account building consumer demand" for Nike in both North America and other markets, Campion said. The company is, however, "mindful" of foreign exchange volatility and the strengthening dollar, he added.

Nike also anticipates gross margin expansion of about 50 basis points or slightly more, driven by strong full-price sales and higher average sales prices in fiscal 2019. The company expects other expenses of about $125 million to $150 million for the year, with an effective tax rate in the mid-teens range. The tax rate guidance could be "volatile" based on the implementation of U.S. federal tax reform, Campion said.

Nike will spend more in the fiscal first half because of investments in the World Cup soccer tournament, Campion said.

More than 60% of the athletes participating in the World Cup are wearing Nike shoes, Nike CEO and President Mark Parker said on the analyst call.