(REUTERS) - Reigning NBA (National Basketball Association) MVP (Most Valuable Player) Russell Westbrook has signed a contract extension to stay with the Oklahoma City Thunder, the team's executive vice-president Sam Presti said on Friday.

Terms were not disclosed, but several media outlets reported the extension was worth US$205 million (S$279 million).

The contract begins with the 2018-19 season, running through the 2022-23 campaign, and gives Westbrook the biggest guaranteed contract in the NBA.

There had been speculation about Westbrook's future with the Thunder given the movement of players throughout the league.

The Thunder, however, enjoyed a strong off-season that landed All-Stars Paul George from the Indiana Pacers and Carmelo Anthony from the New York Knicks.

Westbrook displayed his happiness with the new contract by posting a picture of himself on his Instagram page, wearing an orange Thunder jersey with his arms raised, and the caption of: "WHY NOT?? WHY NOT??"

"Russell's commitment to the Thunder organisation since its inception in 2008 has helped propel us to great heights and stare down great challenges over our first decade," Presti said in a statement.

"We are extremely fortunate to have an athlete, competitor and person such as Russell wear the Thunder uniform."

The 28-year-old Westbrook averaged 31.6 points, 10.7 rebounds and 10.4 assists and set an NBA record with 42 triple-doubles last season.

He joined Hall of Famer Oscar Robertson (1962) as the only players to average a triple-double over an entire season.

The six-time All-Star also won his second scoring crown.