Singapore’s port, already one of the busiest in the world, is facing a sustained period of congestion as vessel diversions to avoid the Red Sea push more container ships to the Asian maritime hub.

Attacks by Yemen’s Houthi rebels in the Red Sea have resulted in shipowners opting not to transit the Suez Canal and taking the longer route around the Cape of Good Hope at the southern tip of Africa. That means they don’t get a chance to refuel or unload cargo at ports in the Middle East, leading to worsening marine gridlock in the waters off Singapore.

The Houthi attacks have reverberated through global supply chains, but the effects are particularly acute in Singapore, which is located on one of the world’s busiest shipping routes linking Europe and the Middle East to China. The growing logjam at the port, a major center for refueling and the redistribution of containers, will result in delays to goods being delivered and will also put more upward pressure on shipping rates.