Tearful Ramos says he wanted to stay at Real Madrid
Ramos said in a press conference he had pushed for a two-year contract extension and when he decided to accept one extra year, the club told his agent and brother "about a week ago" the offer had expired.
The 35-year-old, who will become a free agent on July 1, gave no indication as to where he will play next, although he ruled out joining Barcelona. He also said he was "not contemplating" a return to Sevilla.
Ramos joined Real Madrid from Sevilla for 27 million euros in 2005 and went on to become one of the club's greatest ever players, playing 671 games and winning 22 titles, including five in La Liga and four in the Champions League.
Despite making clear his disappointment over the failed negotiations with Real Madrid, Ramos refused to criticise president Florentino Perez directly, describing their relationship as like a "father and son".
Ramos said bidding farwell was one of the "most difficult moments" of his life.
Afterwards, he answered questions from the media on his own in a press conference room. "I have never wanted to leave Real Madrid," he said.
"I go back to the season during lockdown when we won the title. The club offered to extend my contract but because of Covid, it was delayed.
"In recent months, the club made me an offer of one year, with a lower salary, and I want to emphasise that money was never a problem. I wanted two years for continuity, for me and my family. There was never a financial issue.
"When I finally decided to accept the offer of one year and a lower salary, I was told the offer had an expiration date that I was not aware of."
Ramos insisted he did not know why the offer expired and said he was "really surprised".
"I would have liked to stay here many more years," he said. "Madrid is my home and my family."
Earlier, Madrid's captain opened the door to a return in the future. "This is a 'see you later' because sooner or later, I will come back," Ramos said.
He had just started his speech when he broke down in tears as he begun paying tribute to his family.
Paris Saint-Germain and Manchester City are among the clubs credited with an interest in signing Ramos.
"We never thought about any other team but there have been some calls from interested clubs," he said. "Now we will look for a good option."
He also discarded the option of returning to Sevilla.
"I do not contemplate that option, just as Sevilla does not contemplate it," he said. "It is a different moment now, for them and for me."
But Ramos said he is fit again now and "excited to show his highest level for years to come".
"You have grown as a player and been our iconic captain for years," Perez added.