BANGKOK: Thai zero-waste advocate Thanaboon Somboon never leaves his home without what he calls a full “weaponry” of reusable shopping bags, coffee tumblers and stainless steel straws for his daily battle against single-use plastic.

“I saw news of trash overflowing the world…sea animals dying from eating plastic…I felt I must do something,” says the 48-year-old entrepreneur, who leads an online community of more than 20,000 people seeking to practise a waste-free lifestyle.

But individual efforts alone can’t fully stop the 8 million tonnes of plastic that make their way to the ocean each year, and with four of the five worst ocean polluters in Southeast Asia, the region’s governments must take action, he says.

“Policymaking to address the issue must be treated with urgency as well,” said Thanaboon.

A summit for leaders of the 10-member Association of Southeast Asian Nations (ASEAN) being hosted by Thailand this weekend is expected to adopt the Bangkok Declaration on Combating Marine Debris in ASEAN Region.

Thailand, the current chair of the group, has lauded the declaration as a “big step” for the region, whose coasts have seen whales and sea turtles wash up dead in recent years with large amounts of plastic rubbish in their stomachs.

ASEAN members Indonesia, the Philippines, Vietnam and Thailand are among the five countries throwing the most plastic waste into oceans, according to a 2015 report co-authored by environmental campaigner Ocean Conservancy.

China is the worst offender.

“Every ASEAN country agrees that marine debris is a common problem that we must address urgently,” Wijarn Simachaya, permanent secretary of Thailand’s Ministry of Natural Resources and Environment, told Reuters.

Unlike the European Union’s central bans and targets, Wijarn said the ASEAN declaration will outline broad ideas but it will be up to each country what it would take home to implement.