The Pheu Thai Party is expected to announce a 14-party alliance at the parliament on Monday afternoon.
Pheu Thai secretary-general Prasert Chanthararuangthong said on Monday morning the party would announce its proposed coalition government lineup at a press conference on Monday afternoon. Representatives of about 12 political parties were expected to be there, he said.
He did not know if the Palang Pracharath Party (PPRP) would participate or not.
Sources said there would be 14 parties in the coalition.
Most of the coalition allies would be represented by their leaders and secretaries-general. PPRP leader Prawit Wongsuwon, who is a caretaker deputy prime minister, would not be present but PPRP secretary-general Thamanat Prompow might attend on his behalf, sources said.
Srettha Thavisin, a prime ministerial candidate of Pheu Thai, would not be present but would attend a meeting of Pheu Thai MPs, together with Paetongtarn Shinawatra, another prime ministerial candidate of Pheu Thai, at the party headquarters at 3pm, sources said.
The expected 14-party coalition alliance would have 317 votes in the House and would comprise Pheu Thai with 141 House seats, Bhumjaithai (71), PPRP (40), United Thai Nation (36), Chartthaipattana (10), Prachachat (9), Pue Thai Rumphlang (2), Chartpattanakla (2), Seri Ruam Thai (1), Plung Sungkom Mai (1), Thai Counties (1), New Democracy (1), New (1) and Thai Teachers for the People (1).
It would need 58 more votes in the parliament to ensure a simple majority at Tuesday's expected joint sitting of the 500-member elected House of Representatives and the 249-member appointed Senate, when Pheu Thai will propose a candidate for prime minister.
Pheu Thai came second in the May 14 general election. It withdrew from its alliance with the election winning Move Forward Party, which has 151 House seats, on Aug 2.