Republican Senator Tom Coburn announced on Thursday that he will retire at the end of the current congressional session, two years before his term is up, Reuters reported.
"Serving as Oklahoma's senator has been, and continues to be, one of the great privileges and blessings of my life. But, after much prayer and consideration, I have decided that I will leave my Senate seat at the end of this Congress," he said in a statement.
Coburn, 65, has been suffering from a recurrence of prostate cancer. He announced in November that he would be undergoing chemotherapy. However, he said his decision to retire before his term ends in January 2017 is not related to his illness.
"This decision isn't about my health, my prognosis or even my hopes and desires. My commitment to the people of Oklahoma has always been that I would serve no more than two terms ... I believe it's important to live under the laws I helped write, and even those I fought hard to block," he said.
Coburn is a former member of the House of Representatives and has served in the Senate since 2005. He was re-elected for a second term in 2010. In nine years in the Senate, Coburn earned a reputation as a blunt-speaking conservative who waged war against federal waste and denounced what he called a "dysfunctional Washington."
"As a citizen, I am now convinced that I can best serve my own children and grandchildren by shifting my focus elsewhere. In the meantime, I look forward to finishing this year strong, "he said.
A special election to fill Coburn's seat in Senate will be held in Oklahoma, Reuters reported.
"The people of Oklahoma are lucky to have someone like Tom representing them in Washington - someone who speaks his mind, sticks to his principles and is committed to the people he was elected to serve," President Obama said of Coburn for the 2013 TIME 100.
