Rheo A. Brouillard, chief executive of Willimantic-based SI Financial Group Inc., has been named chairman of a regional “bank of banks” that helps with foreign transactions and other services.

Brouillard, who will remain at SI Financial, took a position at Bankers’ Bank Northeast left vacant when former Banking Commissioner Ralph Shulansky, who had chaired Bankers’ Bank since its inception, died in January.

A long-time member of Bankers’ Bank’s board of directors, Brouillard will be helping lead efforts to find a replacement for Peter J. Sposito, who is retiring as president and CEO later this year, according to The Hartford Business Journal.