Ms McKee died after being hit by a bullet during rioting in the city’s Creggan area on Thursday, April 18, 2019, with dissident republican group the New IRA linked to the killing.
The remarks by the British Prime Minister, who praised her as the embodiment of a “better Northern Ireland”, come as the region marks the 25th anniversary of the Good Friday Agreement.
In a tribute issued by Downing Street to mark four years since the brutal shooting, Mr Sunak said: “Today, we remember Lyra McKee, a journalist who caught the imagination of young people in Northern Ireland.
“In strongly rejecting sectarianism, she embodied the Northern Ireland that I see today – one of realising a better Northern Ireland than what had come before her.
“We stand united against the insidious ideology of those who stole her dreams and what she could have gone on to contribute.”
Former US president Bill Clinton and ex-US secretary of state Hillary Clinton, both in Northern Ireland to attend events reflecting on the past and future of the peace deal, were guests at a special screening in Belfast of a film about Ms McKee.