The Duke of Sussex has said he is "taking a leap of faith" in stepping back from being a senior royal, saying "there really was no other option".
Speaking at an event on Sunday evening, Prince Harry said he and Meghan had hoped to continue serving the Queen, but without public funding.
"Unfortunately, that wasn't possible," he said.
It was his first speech since the couple said they wanted to stand down from being full-time working royals.
The prince said he had found "the love and happiness that I had hoped for all my life" with Meghan, but he wanted to make it clear they were "not walking away".
"The UK is my home and a place that I love, that will never change," he said.
Prince Harry said it was a sign of the pressures he was feeling that he would "step my family back from all I have ever known" in search of "a more peaceful life".
Earlier this month, Prince Harry and Meghan said they intended "to step back as 'senior' members of the Royal Family and work to become financially independent".
On Saturday Buckingham Palace announced that from the spring they will stop using their HRH titles and withdraw from royal duties, including official military appointments.
Beginning his speech at a fund-raising reception in central London for Sentebale, the charity he co-founded which helps children living with HIV in southern Africa, he said: "I can only imagine what you may have heard and perhaps read over the past few weeks.
"So I want you to hear the truth from me as much as I can share, not as a prince or a duke but as Harry."
During his address, the prince said he would always have "the utmost respect for my grandmother, my commander in chief".
"Our hope was to continue serving the Queen, the Commonwealth, and my military associations, but without public funding. Unfortunately, that wasn't possible," he said.
"I've accepted this, knowing that it doesn't change who I am or how committed I am."
Prince Harry and Meghan have both spoken about the difficulties of royal life and media attention, with the duke saying he feared his wife would fall victim to "the same powerful forces" that led to his mother's death.
He told the audience at the reception for Sentebale, which he founded to continue Princess Diana's legacy in supporting those with HIV and Aids, that he felt they took him "under your wing" after she died.
"You've looked out for me for so long, but the media is a powerful force, and my hope is one day our collective support for each other can be more powerful because this is so much bigger than just us," he said.