Following a two-day leaders retreat with his Malaysian counterpart Mr Najib Razak, Singapore's prime minister Mr Lee Hsien Loong announced at a joint press conference in May that the southern terminus of the 330km line would be located at Jurong East, where Singapore's North-South and East-West metro lines converge.

However, in recent days Spad has told the Malaysian media that its preference is for the line to run only as far as the customs, immigration and quarantine complex in Johor Bahru.

"Our understanding is that Malaysia views the commercial premise of the Kuala Lumpur-Singapore HSR project, and with which we agree, as being based on a direct connection between the two city centres," Singapore's Ministry of Transport said in a statement on June 19. "Terminating the HSR in Johor Bahru will not achieve this objective."

The ministry says negotiations are continuing between the two governments on the project's commercial and operating models. Singapore has proposed that the domestic Malaysian high-speed services, which will serve six stations in Malaysia, should be operated separately from direct non-stop trains between Singapore and Kuala Lumpur. Singapore argues that this will give Malaysia autonomy over domestic services while the two countries work together on cross-border services.