Allianz Life Insurance Co., the largest annuity provider in the U.S. with more than $2 billion in sales last year, this week announced a strategic partnership with seven broker-dealers that will add its Allianz Retirement ProSM variable annuity to their advisory platforms.

Allianz Retirement Pro is an insured retirement investment vehicle for clients working with fee-based investment advisors looking for additional, predictable income in retirement.

It will now be offered by Cambridge Investments, Advisor Group which represents Royal Alliance, SagePoint and FSC Securities, Commonwealth Financial Network and Valmark Securities.

"Retirement planning is fundamentally shifting as more financial professionals understand the importance of offering their clients guaranteed income products," Robert DeChellis, president of Allianz Life Financial Services, said in a statement. "Retirement Pro is opening the door for fee-based advisors to do just that, and with the experienced team we've built, we're poised to provide our distribution partners with the complete support they need to be successful in this new market."

Allianz officials said Retirement Pro was specifically designed to help people accumulate, preserve and distribute their retirement assets.

"Establishing strategic relationships with these broker/dealers confirms that Retirement Pro is the right product for that distribution channel, and we expect that the interest we're receiving from other broker/dealers will produce similar relationships in the near future," DeChellis added.

Last year, total annual indexed annuity sales increased 6% to more than $31.4 billion while income annuity sales improved 2% to more than $8 billion. Both retirement income investment products claimed their highest share of investment sales in more than eight years at 48% percent and 11%, respectively.

Allianz topped all providers with more than $2 billion in annuity sales in the fourth quarter. American Equity Investment Life Insurance Co. checked in second at $1.55 billion followed by New York Life at $1.4 billion. Aviva USA and Western National Life rounded out the top five at $1.33 and $1.1 billion, respectively.