Relations between Malaysia and Singapore have warmed in recent months but how will the outcome of Malaysia’s election expected this month affect the ambitious projects that the two neighbors are planning?

Malaysian Prime Minster Najib Razak’s National Front coalition is locked in the tightest ever fight against the Pakatan Rakyat, an alliance led by former deputy Prime Minister, Anwar Ibrahim.

Under the leadership of Razak and Singapore Prime Minister Lee Hsien Long, the two countries have been able to resolve a dispute over the Tanah Melayu railway line, which runs from Singapore to Malaysia. The disagreement was about who owns a valuable part of the railway track but after reaching a resolution the railway line has been shut down in the hope of creating a high-speed rail link between Singapore and Kuala Lumpur by 2020.

“It’s a strategic project for both countries. It will change the way we see each other,” Bloomberg quoted Lee saying after the announcement of the project. He said that Singapore and Kuala Lumpur are “twin cities.”

The logic of good relations is so strong that even the opposition leader Anwar has said he hopes to build closer ties with Singapore and maintain economic, trade and cultural relationships.

Besides the railway line, the two countries are also developing the Iskandar Malaysia industrial complex just across the causeway. It is an ambitious $28 billion dollar project, which encompasses territory nearly three times the size of Singapore.

Anwar’s daughter, Nurul Izzah Anwar, a member of parliament, told Time Magazine that the Iskandar project was “pretty impressive” signaling her party’s support if they win this election.

Still, some Singapore firms are holding back on further investments in Malaysia, including Iskandar, until the outcome of the election is known, as Channel News Asia reported. A new government, especially if it is led by the opposition, may carry out slight policy changes, although nobody expects a complete overhaul.

Ultimately, warming ties between Singapore and Malaysia are largely not at risk but they are still maturing and so constancy is important in maintaining this progress.