BEIJING — A favorite export from China to its neighbors these days are high-speed rail lines designed to make trade routes in the vast stretches of Asia more accessible and fortify Chinese dreams of turning its southern reaches into the capital of mainland Southeast Asia.

But not everyone wants to be bound so close.

A rail project that would pass through the mountains of northeast Myanmar to the coastal plains on the Indian Ocean would give China a shortcut to the Middle East and Europe. For China, the strategic importance of the proposed line can barely be overstated: The route would provide an alternate to the longer and increasingly contentious trip through the South China Sea.

However, the Myanmar government viewed the project as a one-sided proposition and put it on the back burner last month, allowing a memorandum of understanding to lapse. It gave no timeline for when it might reconsider.

“If the project is to be resumed, another memorandum has to be signed,” Ye Htut, the minister of information, said in a telephone interview, “and we have many things to think about before we might do that.”