Sales at fast-fashion giants H&M (HNNMY  ) and its competitor Zara (IDEXY  ) have rebounded to pre-pandemic levels or better, according to sales reports from both companies.

Spain-based Inditex, the owner of Zara and the larger of the two retail companies, reported that third-quarter constant currency sales were up 10% over 2019 levels and maintained that lead through Dec. 10. Swedish company H&M is lagging slightly behind, reporting that its sales in local currencies from September through November had reached pre-pandemic levels.

"The recovery continues to gain momentum," Marcos Lopez, Inditex's Capital Markets director, is quotes in a statement.

Despite the positive sales reports, shares in both companies fell around 3% in early trading on Wednesday, Dec. 15. Analysts suspect that a surge in Omicron variant cases could hammer the fast-fashion retailers' sales come Christmas.

"The main short term risk we see for Inditex is further restrictions on stores and travel flows due to the Omicron variant, especially in southern Europe," RBC analyst Richard Chamberlain told reporters.

According to Chamberlain, an estimated 15% of Inditex sales are made in tourist hubs in major cities, a revenue stream that's particularly vulnerable to travel restrictions.

However, the company produces and ships the majority of its products from its home base in Spain, allowing them to circumvent much of the supply chain disruptions currently occurring across the global economy. Analysts suspect this short delivery time is also one of the reasons the retail giant saw a speedier return to pre-pandemic sales levels.

Inditex's recovery has also been aided by higher sales in China. H&M, meanwhile, was boycotted by Chinese shoppers this summer after making comments expressing concerns over alleged human rights violations occurring in the Xinjiang. China is H&M's second-largest supplier and accounted for 5% of 2020 sales.

"H&M Group is deeply concerned by reports from civil society organisations and media that include accusations of forced labour and discrimination of ethno religious minorities in Xinjiang Uyghur Autonomous Region (XUAR)," the company wrote in a statement. "We strictly prohibit any type of forced labour in our supply chain, regardless of the country or region."

Inditex, the owner of Massimo Dutti, Bershka, and Pull & Bear, is the largest fashion retailer in the world. The company was founded in 1985 in Spain by billionaire Amancio Ortega. In April of 2022, the company's chair will be replaced by Marta Ortega, one of Amancio Ortega's daughters.The announcement of former-CEO Pablo Isla's resignation shocked investors in November of this year.