The Live Your Life star has written a series of open letters for The New York Times, one to Obama, another to President-elect Donald Trump and to America's citizens, and the first, to Obama, was published on Friday (06Jan17).

In the letter, he praises Obama for fighting for equality and acceptance and promised his legacy would live on past his time in office, which ends on 20 January (17).

"You entered humbly into our worlds from the streets of the South Side of Chicago and galvanized a generation," he wrote. "Many of US did not know your name, nor did we truly understand the impact you would have on the world in the years, months and days that followed.

"As I reflect, I am filled with gratitude, outrage, grief, anger, humility and appreciation, both for the things you helped bring to light and the many things we still have yet to realize... Not only did you impact a nation, but you defined a culture and you shook up and woke up a generation."

He also recalls agreeing with late rapper Tupac Shakur when he said the U.S. wasn't "ready for a black president" in his hit Changes, which was released posthumously in 1998. However, he changed his mind when Obama "brought US the audacity of hope and reminded US that yes we can."

T.I. adds that the U.S. public must get over the shock about Trump's presidency and continue to fight for causes that Obama championed.

"We will forever be grateful to you and your family," he concludes. "WE will continue to stand with you and alongside those who make a personal investment in US... We will continue to remind ourselves that, Yes, We still can!"

Obama and First Lady Michelle hosted a farewell party at the White House on Friday (06Jan17) which was attended by celebrity guests including Robert De Niro, Meryl Streep, Paul MCCartney, Stevie Wonder, Tom Hanks, Chris Rock, and George Lucas, according to Mail Online.

Other stars including Nick Jonas, Jordin Sparks, and Chance the Rapper also confirmed their attendance on social media.