Thai prosecutors have recommended that both the ruling Thai Rak Thai party and the main opposition Democrat party be disbanded for violating election laws.
A spokesman for the Attorney General's office said prosecutors had unanimously agreed that the two parties, along with three others, had committed violations.
The Constitutional Court must now decide if they should be disbanded.
Correspondents say this possibility, though unlikely, highlights continuing uncertainty after April's election.
The courts invalidated the controversial poll, and a new election date has tentatively been set for 15 October.
Thailand's Election Commission initially put forward the charges against the two main parties, ruling that they had violated separate election laws.
The case was then passed to a committee appointed by the attorney general's office.
"Prosecutors have decided that the cases should be submitted to the Constitutional Court to consider dissolving the parties," the attorney general's spokesman Attaphon Yaisawang told reporters on Tuesday.
Prime Minister Thaksin Shinawatra's party, Thai Rak Thai, is accused of illegally financing smaller parties to run against it, to make the polls appear more legitimate after the main opposition parties boycotted the vote.
Since protests earlier this year, the nation has been in limbo
The Democrat Party is accused of violations relating to its decision to boycott the poll.
Analysts say the accusations will only add to Thailand's political impasse.
Because the April election failed to form a parliament, Thailand's revered king made a rare intervention, calling on the country's courts to take action. The judges quickly ruled that the entire election was invalid and ordered a re-run.
The courts and the election commission - which has been heavily criticised over the April poll - are still trying to agree on a definite date for this next vote.