The cabinet has awarded 100 billion baht in contracts for two monorail projects to BSR Joint Venture.
Analysts said BSR could opt to raise funds for the projects through the Stock Exchange of Thailand (SET) instead of with loans.
Nathporn Chatusripitak, an adviser to the Prime Minister's Office, said the two monorail projects are the 34.5-kilometre Pink Line, worth 53.5 billion baht, and the 30.4km Yellow Line, worth 52 billion baht.
The Pink Line will run from Nonthaburi's Khae Rai to Bangkok's eastern Min Buri district, while the Yellow Line will run from the Lat Phrao area to Samrong in Samut Prakan.
BSR is a venture of BTS Group Holding Plc, Sino-Thai Engineering and Construction Plc (STEC) and Ratchaburi Electricity Generating Holding Plc (Ratch).
BTS holds a 75% stake in the consortium, while Sino-Thai owns 15% and Ratch 10%.
"The joint venture is likely to raise funds via the SET, as the cost of funds is much cheaper than for loans," one analyst said.
Another analyst added: "The joint venture could opt to raise funds by launching an initial public offering or offering a new infrastructure fund on the SET."
Mr Nathporn said the two monorail lines are to be developed under the Public Private Partnership (PPP) Net Cost model.
Under the PPP Net Cost arrangement, the government will be responsible for the acquisition of land and provide funding for up to 20.1 billion baht for civil works on the Pink Line and up to 22.4 billion on the Yellow Line.
BSR will carry out construction, install machines and electricity systems, and provide train operation and maintenance services.
The total investment cost is 53.5 billion baht for the Pink Line and 51.8 billion for the Yellow Line.
As a result, the government will invest 43 billion baht in the two projects out of the 100-billion-baht estimated cost.
Of the 43 billion baht, 20 billion will be for the Pink Line and 23 billion for the Yellow Line, to be gradually paid to BSR over 10 years.
A source at Sino-Thai said the construction costs of the two lines are estimated at 40 billion baht.
The source said that while Sino-Thai has been awarded major infrastructure projects, the company is continuing to pursue a conservative strategy by strengthening its financial status with strong cash flow.
"Cash flow is the heart of the construction business, and that's why Sino-Thai is still focused very much on strengthening our cash flow," the source said, adding that the company's cash flow is about 10 billion baht.
The source said Sino-Thai has a historically high backlog of projects worth 101.4 billion baht that will ensure substantial work to provide revenue for about five years.
The company posted a small drop in net profit in the first quarter of this year, with 249 million baht versus 268 million a year earlier, the source said.
Sino-Thai reported a net profit of 1.4 billion baht for the whole of 2016, down from 1.5 billion in 2015.
The source said the company plans to maintain a profit of 1 billion baht annually over the next few years as the economy recovers.
"A flat profit of 1 billion baht a year is strong enough to allow the company to pay dividends to all shareholders every year and also strengthen the company's financial status to be ready for full competition and aim for higher growth over the next few years," the source said.
STEC shares closed yesterday on the SET at 26.25 baht, unchanged, in trade worth 64.6 million baht.