The role of the monarchy in Thailand is at the core of a looming deadlock that could tip Southeast Asia's second-largest economy into crisis, with reformers once again vying to dislodge the grip on power of the royalist military establishment.

Despite a stunning victory with its allies over pro-military parties in a May 14 election, the progressive Move Forward party led by Pita Limjaroenrat faces an uncertain path to government.

The main reason is that part of Move Forward's political platform is the once-unthinkable proposal to amend Thailand's lese-majeste law, Article 112 of the criminal code that punishes insulting the monarchy with up to 15 years in prison.