In a brief statement Sunday night, Prime Minister Kamla Persad-Bissessar said that Warner offered to resign from her Cabinet and that she accepted his decision. She had raised eyebrows last June when she named Warner as the national security minister, calling him a "man of action."
"I wish to thank Mr. Warner for his service to the government and people of Trinidad & Tobago," Persad-Bissessar said, adding that she had advised Trinidad's governor general to appoint another lawmaker to lead the security ministry.
Warner's resignation came shortly after an ethics panel of the Confederation of North and Central American and Caribbean Football released a report charging that Warner and a former secretary general of the group enriched themselves through fraud during their terms with the organization, known as CONCACAF.
Warner has repeatedly dismissed the various allegations against him and denies any wrongdoing. He could not immediately be reached for comment Sunday night. He remains a member of Parliament.
Warner resigned as CONCACAF president in June 2011 after a former secretary general of the regional body accused him and then-Asian confederation head Mohamed bin Hammam of attempting to bribe Caribbean delegates $40,000 each to vote for Bin Hammam in the election for president of FIFA, the international soccer organization.
Chuck Blazer, the former CONCACAF secretary general who made the accusations, was the other official accused by the organization's ethics and integrity committee of corruption in a 113-page report presented by the group's congress in Panama City.
Committee member David Anthony Cathcart Simmons has accused Warner of misappropriating at least $15 million by compensating himself with CONCACAF funds without authorization after his last contract expired in July 1998.
Warner oversaw North American and Caribbean soccer for almost three decades. When he resigned in June 2011, he avoided investigation into the bribery scandal tied to the FIFA presidential election.
Among the other complaints made against him during his leadership positions in the sport, he has been accused of mismanaging nearly $1 million in FIFA funds slated for a reconstruction project in Haiti.
In Trinidad, some political analysts said Warner's resignation as the twin-island country's top security official was inevitable given all the accusations.
"The ceaseless allegations have been going on too long. They have affected the public psyche, which has been under siege. It will hurt the government—the PM took too long—but will win some friends for her that some action has been taken," said Winford James, a political analyst and newspaper columnist.
In recent days, Trinidad opposition leader Keith Rowley had demanded that Warner resign. On Sunday night, he criticized the prime minister for not demanding Warner's resignation and instead waiting for him to offer to step down.
"So the prime minister still did not act. Warner resigned," Rowley said.
But others said there was likely behind-the-scenes maneuvering that led to Warner's decision to step down.
"He was persuaded it was best to go. There is going to be negative fallout for the government as the opposition and civil society groups will say the prime minister waited too long to act," said Bishnu Ragoonath, a lecturer at Trinidad's University of the West Indies.
Many people were surprised when Warner was appointed security minister.
Shortly afterward, he was sharply criticized for dispatching troops and riot police to remove a protest camp built by environmentalists. He also made headlines when he announced he hoped to stop the release of crime reports and statistics, arguing that publicizing such information encouraged people to commit more crime.
Associated Press writer David McFadden in Kingston, Jamaica, contributed to this report.