Port congestion in some of Asia’s busiest trade hubs may persist into August, as ships diverting away from the region’s most clogged maritime gateways cause bottlenecks at others.

Singapore, the world’s busiest transshipment center, for weeks has dealt with longer-than-usual lines of vessels waiting for berth space. Among the reasons: ships sailing the long way around Africa to and from Europe — avoiding Houthi attacks in the Red Sea — are stopping at fewer Asian ports and processing more cargo through Singapore.

The pileup in Singapore has eased somewhat “but only because vessels are omitting calls at the port,” according to Tan Hua Joo, a container market analyst at Linerlytica. Some were diverted to Port Klang and Tanjung Pelepas in Malaysia “and this has shifted part of the congestion there,” he said in an email.

Overall, the congestion issues have “eased slightly since mid-June but the problem will take a least one more month to be resolved,” he said.

Asia’s ports remain the biggest hot spots for traffic backups, according to Linerlytica. Of the idled container capacity globally that’s waiting to dock, 23% is in Southeast Asia, 20% is in the Middle East and 11% is in the Indian subcontinent.

In addition to Singapore, Malaysia’s Port Klang is struggling to keep up, as is the Chinese port of Shanghai.

According to figures released Tuesday by Hapag-Lloyd AG, the world’s fifth-largest container carrier, the wait for berth space in Port Klang has increased to as long as five days, more than double the wait posted June 12. Shanghai is showing waits of as long as three days, down from four days.

Ships trying to visit Colombo, Sri Lanka, or Dubai are looking at delays of as much as three days, according to Linerlytica.