China’s export growth slumped in April to its lowest level in almost two years, customs data showed Monday, as a COVID-19 resurgence shuttered factories, sparked transport curbs and caused congestion at key ports.

The data shows the extent of growing damage as the world’s second largest economy confines millions to their homes — particularly in key business hub Shanghai — to stamp out its worst COVID-19 resurgence since the early days of the pandemic.

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Beijing has persisted with a strict zero-COVID policy involving lockdowns and mass testing, but the economic costs are mounting as manufacturing hubs and supply chains atrophy under gruelling restrictions.

Export growth plunged to 3.9 percent on-year last month, the Customs Administration said on Monday.

While this was above analysts’ expectations of 2.7 percent growth according to a Bloomberg poll, it marked the lowest rate since June 2020.

Import growth was flat in April, an improvement from a 0.1 percent contraction in March, as Chinese consumers remain hesitant under a welter of restrictions across the country.

Customs spokesman Li Kuiwen tried to strike an upbeat note on Monday saying the economy still has room to make a turnaround and that its “positive fundamentals” remain unchanged.

In April, China’s biggest city Shanghai was almost entirely sealed off as it became the epicenter of the country’s worst coronavirus resurgence, with many factories halting production and trucker shortage causing goods to pile up at its port.

Restrictions are also creeping in other cities, including the capital Beijing.

While top leaders have offered words of reassurance for tech, infrastructure, and jobs, analysts have warned that the zero-COVID-19 strategy remains a dominant challenge to growth and stability.

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