Arizona Sen. John McCain said Monday that he plans to run for a sixth term in 2016. 

The Republican revealed his plans in an interview with NBC News, saying that his Senate career is "just getting started."

McCain, 78, will be 80 years old on Election Day 2016. He is currently the eighth-oldest senator and has run for president twice, in 2000 and 2008. 

In the interview with NBC, McCain criticized President Barack Obama's foreign policy, saying that he has "never been more concerned about the security of this nation because of the feckless leadership of the president of the United States." McCain became chair of the Senate Armed Services Committee after the GOP took control of the upper house in this past November's election. 

Tea Party groups could see McCain as a potential target for a primary challenge, as some conservatives have have criticized him as too liberal. In 2010, McCain easily saw off former Congressman J.D. Hayworth in the Republican Senate primary. It was the first time McCain had faced a non-write-in primary challenge since being elected to the Senate in 1986.

To win, McCain said he will emphasize issues in Arizona, such as the ongoing drought, his work to benefit a copper mine and legislation to reform the Department of Veterans Affairs.

The VA was thrown into turmoil last year amid allegations of misconduct and cover-ups at the VA hospital in Phoenix. Investigators say veterans' health was jeopardized when employees covered up long wait times for patients.

The Associated Press contributed to this report.