A consumer passes by a Dior store in Guangzhou, capital of South China's Guangdong Province. File photo: CFP

French luxury brand Dior sold out all of its limited edition Lady Dior bags on Chinese mobile app WeChat on the first day of what was to be a four-day online marketing campaign, a sign that experts said on Tuesday shows online is the new way to go for upmarket brands to reach local customers.

On Monday, the luxury brand offered via its official WeChat account the limited edition Lady Dior Small China Valentine bag for the upcoming Qixi, or Chinese Valentine's Day, which falls on August 9 this year.

According to the company, the pink-hued purse would only be available online until Thursday at a price of 28,000 yuan ($4,217).

The campaign makes Dior the first luxury brand to sell bags through the WeChat platform, representing a step forward toward social media.

"Dior produced a few hundred of the limited edition bags for the campaign, but due to high customer demand, we sold out in a day," a member of the customer service staff at Christian Dior told the Global Times on Tuesday.

She mentioned that Dior's bricks-and-mortar boutiques started selling the same bag in black at the same price from Tuesday.

As the global luxury industry has been facing strong headwinds in recent years, it may become a trend for these brands to use social media channels such as WeChat to get closer to their customers, experts said.

"It was a good effort for Dior, and in the future, WeChat may become an important marketing channel for Dior to promote products and interact with customers," Liu Dingding, an independent industry analyst, told the Global Times on Tuesday. "And I think many other luxury brands may follow suit to try more channels so as to reach a wider range of customers."

Dior is not the first luxury brand to use WeChat to test the waters. Since 2015, Cartier, IWC, Montblanc and Longchamp have launched marketing platforms on WeChat to promote customized services and online exclusive discounts.

Compared with other e-commerce platforms, high-end luxury brands have shown an increasing fondness for WeChat, which has something to do with its massive user base, Liu noted.

As of the end of the first quarter of 2016, the number of monthly active WeChat users reached 762 million, according to data from statista.com.

"Luxury brands can't pass up a channel that covers so many people," Liu said.

"What's good in social media is that it offers a more flexible channel for brands to reach their customers in the way they want," Li Chengdong, an independent e-commerce strategy analyst, told the Global Times on Tuesday.

"Times have changed. It wasn't that long ago that most luxury brands kept their distance from e-commerce, and official websites were nothing more than image display platforms," Li noted.

But the Internet is an irresistible retail force, and an increasing number of younger customers have the habit of shopping online, Li said. Customers are on the Internet, and sellers should be there too, no matter what they sell.

According to the annual Altagamma-McKinsey Digital Luxury Experience Observatory report released in October 2015, online sales of luxury goods could triple to 70 billion euros ($78.17 billion) by 2025, accounting for 18 percent of total luxury sales.

Some 36 percent of respondents in the Chinese mainland said in 2015 that they were willing to buy luxury goods online, up from 24 percent in 2014, according to the 2015 China Luxury Forecast issued by market research firm Ipsos Group in November 2015.