Japan's Honda and Nissan said Monday they had embarked on formal merger talks that would create the third-largest car manufacturer globally with sales of as much as $191.4 billion and more than $19 billion profit.

Honda Motor Co. and Nissan Motor Co. plan to merge under a holding company with the top executives chosen by Honda in a historical reshuffling of Japan’s auto industry meant to keep the country’s second- and third-largest players competitive amid a global onslaught of new competitors and technologies.

Speed limits are usually intended to prevent drivers from going too fast. Occasionally, though, they warn against bumbling along the road too slowly. Honda Motor boss Toshihiro Mibe and his Nissan Motor counterpart Makoto Uchida will need reminding of this if they don’t soon shift out of low gear for the tie-up they proposed on Monday.