Disgraced designer Galliano was fired from his job at Christian Dior and his eponymous label in 2011 after he was caught on video making anti-Semitic remarks during an argument in Paris.
He explained he had been battling alcohol and drug addictions and travelled to America to spend time in rehab. Since then he has been out of the spotlight, save for creating Kate Moss' wedding dress in 2011.
It has now been confirmed Galliano is to enjoy a temporary residency at de la Renta's New York studio. The British designer will help the older style stalwart as he prepares for his New York Fashion Week show.
"John and I have known each other for many years and I am a great admirer of his talent," de la Renta told WWD.
"He has worked long and hard on his recovery and I am happy to give him the opportunity to re-immerse himself in the world of fashion and re-acclimate in an environment where he has been so creative."
There has been much speculation about Galliano's next month since his downfall, with reports he was in the running to head up the re-launched Schiaparelli. He explained he has tried not to let the constant rumours affect his recovery.
"I am an alcoholic," he said. "I have been in recovery for the past two years. Several years prior to my sobriety, I descended into the madness of the disease. I said and did things which hurt others, especially members of the Jewish community. I have expressed my sorrow privately and publicly for the pain which I caused, and I continue to do so. I remain committed to making amends to those I have hurt.
"I am grateful to Oscar beyond words for inviting me to spend time with him in the familiar surroundings of a design studio. His support and faith in me is humbling."
The move has led to speculation Galliano is being lined up to take the reins when de la Renta retires. The older designer has dismissed the idea, insisting he has no plans to stop working.
He explained he likes to have creative people near him when he is working, which is where Galliano is stepping in.
"While I'm working on a collection, I sit with all of my assistants around me," de la Renta said.
"I'm not a loner. I listen to everyone. I wish the Virgin Mary would come and sit next to me. I love to be surrounded by people.
"I think John is doing all the right things. Everyone in life deserves a second chance, especially someone as talented as John. I think that life is about forgiving and helping people."
The Anti-Defamation League which was set up to battle anti-Semitism has released a statement about Galliano's plans. The organisation's director Abraham H. Foxman fully supports the designer's decision to return to work and has praised him for his recovery efforts.
"We believe that individuals can change their hearts and minds as long as they demonstrate true contrition," Foxman said. "Mr Galliano has worked arduously in changing his world view and dedicated a significant amount of time to researching, reading and learning about the evils of anti-Semitism and bigotry. Along his journey to recovery he met with us on numerous occasions. He has accepted full responsibility for his previous remarks and understands that hurtful comments have no place in our society."