WASHINGTON (AFP) - Senator Harry Reid, the combative leader of the Democrats in the United States Senate, said on Friday that he won't be seeking reelection in 2016.

The 75-year-old Nevada senator suffered serious injuries while exercising in his Las Vegas home in January that left him with broken facial bones and deep bruising around one eye.

In a video announcing his retirement, Sen Reid said the accident had nothing to do with his decision to step down, but noted that his recovery had given him some unusual "down time".

"I have had time to ponder and to think," he said. "We've got to be more concerned about the country, the Senate, the state of Nevada than about ourselves. And as a result of that, I'm not going to run for reelection."

Sen Reid's retirement next year will come three decades after he was first elected to the Senate.

He served as Senate majority leader from 2007 to 2015. After the Democrats lost their majority in elections last November, he became Senate minority leader.

"We have to make sure that the Democrats take control of the Senate again," Sen Reid said. "I feel it is inappropriate for me to soak up all those resources on me when I could be devoting those resources to the (Democratic) caucus, and that's what I intend to do."

In 2010, Sen Reid shepherded President Barack Obama's signature healthcare reform legislation, dubbed "Obamacare," through the Senate.

His relationship with the Republicans has gradually deteriorated, culminating with a controversial decision to change centuries-old Senate rules around filibusters.