China's foreign trade ran into difficulties last year, with imports and exports both experiencing year-on-year declines.

Despite encouraging figures last month, the trade picture for this year remains gloomy, according to Customs data released on Wednesday.

"The double decrease in imports and exports is due to economic slowdown and weak demand throughout the world," said General Administration of Customs spokesman Huang Songping.

Chinese exporters faced challenges last year, Huang said, with 2015 exports totaling 14.14 trillion yuan ($2.28 trillion), down 1.8 percent from 2014 and the first export decline since 2010.

Imports fell by 13.2 percent to 10.45 trillion yuan last year, and the combined volume of imports and exports stood at 24.59 trillion yuan, a 7 percent year-on-year decline.

Huang forecast that China's foreign trade this year will remain at the same level as last year, despite encouraging numbers in December, when exports increased 2.3 percent to 1.43 trillion yuan.

Weak global demand and the dropping prices of bulk commodities have contributed to the decrease in trade.

Huang added that his department will pay close attention to currency fluctuations.

The trade picture may remain gloomy this year, as China is still going through economic restructuring and a manufacturing upgrade.

Moreover, China is losing its edge on cheap labor costs, said Tong Jiadong, vice-president of Nankai University.

"The competition is getting more intense. As the country tries to replace outdated manufacturing capacity, new trading methods and high-end products with more added value need to be encouraged," Tong said.

Guangzhou Bosma Optoelectronic Technology Co also witnessed its sales and profits declining, due to decreased demand in traditional markets such as Europe and the US.

But Zeng Dexiang, president of the company, said he remains optimistic, since his company has diversified its product portfolio with cloud-computing segments.

In Wenzhou, the country's trade hub in East China's Zhejiang province, clothing enterprises are facing mounting difficulties in exporting, with a year-on-year plunge of 18 percent last year, according to Chen Qixiang, secretary-general of the Wenzhou Chamber of Clothing Commerce.

This is partly because of the slower-than-expected recovery of European economies and the unstable situation in the Middle East, Chen said.

Dongyi Shoes Co, an export-oriented shoe manufacturer in Wenzhou, is also witnessing a sharp yearly decline of up to 10 percent in export volume, as well as fewer orders from abroad.

"We have no other option but to switch from traditional strong markets, such as Russia and US, to more emerging ones like the UK, Germany and even Brazil, for more partners and profits," said Chen Xi, general manager of Dongyi.

The shoemaker has benefited from the depreciation of the renminbi last month, but Chen contended it would be more preferable for the currency to stay stable. "Otherwise, it will be difficult for exporters to calculate and set the price range to avoid losses," said Chen.