If government lawmakers have their way and pass the charter amendment bill in its third and final reading today, the hot potato could land in the prime minister's lap.
A source in Government House said the stalemate could heighten if the bill is taken up and cleared despite a Constitution Court order to suspend debate on the bill while judges look into accusations that the law would pave the way for the overthrow of the monarchy.
The source said Pheu Thai is wary of a possible backlash from a third reading, which could shift political pressure on to Prime Minister Yingluck Shinawatra.
Section 150 of the constitution requires the premier to submit a bill to the King through the Privy Council within 20 days of legislation being approved by parliament.
Senator Kamnoon Sitthisamarn warned that if the bill passes its third reading while the legal dispute over the bill remains unresolved, it could create problems for the King, who would have to endorse the law.
House Speaker Somsak Kiatsuranont should rise to the occasion and call off the parliament session today, he said.
If Mr Somsak sits on his hands, the country will slip into a political crisis far bigger and more complicated than in the past, the senator warned.
Those who initiated the bill should instead provide the court with arguments refuting the anti-bill petitions, he said.
Already, both sides of the political divide have argued for and against the Constitution Court's injunction. The court insisted debate on the bill should cease until judges establish whether there are grounds to proceed on petitions against the bill _ which complainants say would set the stage for the overthrow of the constitutional monarchy.
Many government MPs and some legal experts took the court to task, claiming it had no power to admit the petitions _ which they say must instead be submitted only to the attorney-general _ or to issue the injunction.
Ruling Pheu Thai Party's MPs have threatened to ignore the injunction and put the bill on today's meeting agenda in parliament.
However, it is not clear if they will follow up on the threat.
PM's Office Minister Woravat Au-apinyakul said MPs will debate whether the injunction binds parliament.
No date for the third reading of the vote has been fixed. However, he said the vote is inevitable and there is no reason to stall it.
The source said some government MPs feel the prime minister should acknowledge the chances of political or legal repercussions if she forwards the bill, heavily mired in legal conflict between Pheu Thai MPs and the Constitution Court.
There is also the question of whether privy councillors will take the bill to the King if Ms Yingluck submits it.
Other government MPs feel the third reading of the vote should be delayed until after the Constitution Court decides if the petitioners have sound grounds for their complaints, and, if they do, concludes its deliberation of the subsequent case.
But the source said the wait may be futile because there is no guarantee the court's verdict would favour the bill.
Also, there is a possibility that current MPs' support for a speedy passage of the bill will ebb if the affair drags on.
Somkit Lertpaithoon, Thammasat University rector and former charter drafter, said the Constitution Court's order must be followed to keep alive the rule of law.
He slammed law academics who advised MPs to defy the court's order.