Pheu Thai party leader Sudarat Keyuraphan (L) and Future Forward Party leader Thanathorn Juangroongruangkit in Bangkok on March 27, 2019.
Bangkok, Thailand CNN  — 

Pro-democracy parties battling to block the military’s return to power after Thailand’s first election since a 2014 coup said Wednesday they have secured enough seats to form a government.

The main opposition Pheu Thai party, which was ousted before the coup, and six other parties announced they had forged a coalition accounting for 255 seats in the 500-member lower house of parliament.

“We want to stop the regime from hanging on to power,” Pheu Thai’s prime ministerial candidate Sudarat Keyuraphan told a press conference

A military junta has ruled Thailand for the past five years under coup leader turned Prime Minister Prayut Chan-o-cha.

In response, Deputy Prime Minister Wissanu Krue-ngam called the anti-junta coalition a “merely psychological strategy that will not bear fruit.”

The outcome of Sunday’s election is still unclear, with no party taking a decisive lead but both leading parties – Pheu Thai and the pro-military Palang Pracharat – claiming the right to form a coalition. Persistent delays in the release of the final results have fueled confusion.

Representatives of the pro-democracy coalition told reporters that together they could muster 255 seats based on preliminary results.

“We have obtained the majority and received consensus from the people,” said Sudarat. In the lower house, 350 seats will be filled with winners in the various constituencies and the remaining 150 through a party list proportional system.

Parties are still waiting to hear how many seats they will be allocated under the proportional system, which could be decisive in reaching a majority.

Pheu Thai had 137 constituency seats according to the latest count on Monday. Palang Pracharat – which wants junta leader Prayut to return to power – had 97 seats, according to the Election Commission. Official final results will not be announced until May 9.

Pheu Thai is the party of populist former Prime Minister Thaksin Shinawatra, toppled by a coup in 2006, and of his sister Yingluck. She also become prime minister but was impeached just before the military coup in 2014. Thaksin and leaders connected to him have won every election since 2001.

Palang Pracharat is also intent on forming a coalition government on the basis that it is leading the popular vote despite lagging in the number of constituency seats according to Monday’s tally. The party also has the backing of the 250-member Senate or upper house, whose members are all appointed by the military.

Future Forward, which shot up in the polls after winning support from the younger generation and looks set to become the third largest party, joined the pro-democracy alliance on Wednesday.

Its leader Thanathorn Jungrungruangkit demanded that the Election Commission release the returns from each polling station so the figures could be scrutinized.

There are mounting concerns over irregularities in Sunday’s poll, including nearly 2 million votes that were disqualified as “bad ballots.”

On Tuesday election watchdog Open Forum for Democracy Foundation said the poll was “not free and fair” while another group, The Asian Network for Free Elections, said the process “displays fundamental democratic shortcomings.”