US broker Arthur J Gallagher has signed off on an agreement to acquire a controlling interest in major loss adjuster GAB Robins North America.

The deals will see the broker taking a majority share of third-party administrator assets and managed care operations.

Following a transitional period, Gallagher expects the deal will generate more than $US45-$US50 million ($46.4-$51.6 million) in revenue.

GAB Robins in Australia became part of the international Cunningham Lindsey group in February.