BANGKOK • The controversial multi-billion dollar Kra Canal project is not a priority for Thailand's government and is under review, an official spokesman clarified.

Lieutenant-General Sansern Kaewkamnerd was responding on Sunday to calls by influential figures to support construction of the waterway across the country's south that will connect the Gulf of Thailand to the Andaman Sea, and shorten the marine route between the Pacific and Indian oceans.

Mr Sansern said Thai Prime Minister Prayut Chan-o-cha had insisted his government did not have a policy on the project.

"There are still other problems in the area, therefore they (the other problems) must be prioritised," he said in a statement.

He also urged the people in southern Thailand to exercise caution over messages supporting the canal project, referring to a group that has been rallying the public to endorse the project online and support specially-composed songs about the waterway.

"Prime Minister Prayut Chan-o-cha has emphasised the (pro-canal) movement has not been not approved by the government and the project is still pending a study," said Mr Sansern, according to the Bangkok Post.

He said the government was still weighing the pros and cons of the 100km-long canal, which could provide an alternative route to the Strait of Malacca that will bypass Singapore, and cut the sea journey between the Middle East and east Asia by at least 1,000km.

The issues being considered include security and cost.

Supporters of the project have called for the canal to be built quickly, as it will be a boon to the shipping industry with commercial ships on the Indian-Pacific ocean route.

However, security observers in Thailand have voiced concerns about the canal's location in the restive south, which for two decades has seen a simmering conflict between government forces and Muslim insurgents.

They are also worried such a canal would split the country into two and eventually lead to southern Thailand breaking away from the rest of the country.

BERNAMA