New Jamaica prime minister Portia Simpson Miller has pledged to replace the Queen as head of state and make the island a republic.
She was speaking as she was sworn in for the second time as prime minister.
Jamaica declared independence from Britain in 1962 but remains within the Commonwealth.
"I love the Queen; she is a beautiful lady," she quipped, before speaking to the audience in Jamaican patois: "But I think time come."
She also said she will replace the Privy Council in London with the Trinidad-based Caribbean Court of Justice as Jamaica's highest court of appeal. She said this will "end judicial surveillance from London".
The new prime minister, whose one and a half year-long first stint in office ended in 2007, took the oath of office before roughly 10,000 guests on the grounds of the rambling, colonial-style mansion that is the official residence of the governor-general.
The 66-year-old politician scored a dramatic victory in last week's national elections, leading her left-leaning People's National Party to a two-to-one margin in Parliament over the centre-right Jamaica Labour Party.
The plain-spoken, charismatic Simpson Miller, the island's first female prime minister, takes over from Andrew Holness, a 39-year-old Labour MP who was leader for just over two months.
"After being tested and tempered, I stand before you today a stronger and better person prepared to be of service to my country and people," she said at the start of a spirited 45-minute speech.
She vowed her government will "ease the burdens and the pressures of increasing poverty, joblessness and deteriorating standards of living" while also pursuing a tight fiscal policy and forging strong partnerships with the private sector and international partners such as the International Monetary Fund. Jamaica is a cash-strapped island with a punishing debt of roughly 18.6 billion dollars (£12 billion) , or 130% of gross domestic product.