Khan hasn't fought since suffering a sixth-round knockout defeat, in a middleweight world title fight, to Saul "Canelo" Alvarez in May 2016.
"I'm determined to win another world championship and I'm confident I've got the right team behind me to help me do so".
In November a year ago, Khan said he still wants a fight with Kell Brook, but admitted they both need to rebuild their careers with wins before settling their long-running rivalry.
Speaking to SunSport, the 31-year-old said: "When that fight didn't happen it put me on a really bad downer".
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Having previously claimed "I just don't like Eddie Hearn", Khan has put his issues with the promoter to bed and agreed terms on a contract.
A celebrity detox in the television jungle has cleared Amir Khan's mind for a comeback in the more down-to-earth surroundings of Liverpool, on April 21.
"One of the biggest stars in world boxing is back at a time when British boxing is booming", Hearn said.
"Amir is one of the biggest names in the sport of boxing and his return on April 21 will be the first time he has boxed in the United Kingdom in seven years", Hearn said. "I was in the jungle, thinking very hard not listening to other people, thinking about where I wanted to be in my life", he said.
"The plan is to box in April and then again in August or September in preparation for a super fight in winter 2018", Hearn said Wednesday, according to a story posted to the website of London's Daily Mail. Eddie will probably be my last promoter now'.
It will also be five years since Khan last fought in the United Kingdom, and since then Hearn has repeatedly tempted to lure him into a fight with rival Kell Brook, contributing to the tension between them.
Amir Khan's father Shah Khan said that his son was focussed on training and getting ready for the next big fight and had full support of all his family.
"Pacquiao, Garcia and Peterson are what we are looking at, but when Eddie and I spoke we talked about Kell Brook being the target", he added.