Phuket’s Kathu–Patong Tunnel Project Revised, Returns to Cabinet Approval Stage

Phuket's long-awaited Kathu–Patong tunnel remains one of the island's highest-priority transport projects, but revised plans have pushed it back to an earlier stage of the approval process, requiring a new review by Thailand's Cabinet.

The change became public during a recent visit to Phuket by Deputy Transport Minister Sapphasit Boonyamanee, who confirmed that the project had been modified and must now be resubmitted to the Cabinet. If approved, officials expect the proposal to receive government endorsement no earlier than the fourth quarter of 2026.

The revision effectively resets much of the project's previous progress. Earlier versions of the tunnel had already advanced beyond Cabinet approval and were being prepared for the contractor bidding process.

However, following changes introduced by the Ministry of Transport, the project has returned to the government approval stage.

Despite the delay, Boonyamanee emphasized that the government remains committed to building the tunnel.

"The Kathu–Patong section is a project local residents have requested for many years. It is essential for reducing traffic congestion, improving transport efficiency, and strengthening Phuket's infrastructure."

He added that detailed studies have made significant progress and that, once Cabinet approval is obtained, construction is expected to begin immediately, with completion estimated to take around four years.

The tunnel will form the first phase of the planned Phuket Expressway, the island's first toll motorway.

The expressway is divided into two sections:

• Phase 1 – Kathu–Patong Expressway: A four-kilometre route featuring a tunnel beneath Khao Patong. Earlier this year the previous version had already progressed to procurement preparations, but it must now undergo Cabinet approval again.

• Phase 2 – Mueang Mai–Koh Kaew–Kathu Expressway: A 30.6-kilometre highway connecting the airport area with Kathu and including a branch toward Bypass Road in Koh Kaew. This section remains at the detailed design stage.

The most significant design modification involves reducing the width of the tunnel. According to the Ministry of Transport, the adjustment was made to keep the project within budget following rising construction and material costs.

During his visit, Boonyamanee also inspected the planned tunnel entrance together with Phuket Member of Parliament Chalermpong Saengdee, who has repeatedly advocated for accelerating the project.

Saengdee said the latest revision raises important questions and called on authorities to clearly explain why the tunnel's dimensions were changed and how the redesign could affect both operational efficiency and safety.

He noted that the project is now awaiting Cabinet approval before the Expressway Authority of Thailand (EXAT) can move forward with implementation.

The completion date for the full Phuket Expressway, originally targeted for 2030, is now expected to shift to 2031.