An overview of the Oakland-Alameda County Coliseum before the start of an NFL game between the Oakland Raiders and the Denver Broncos in Oakland, Calif., Monday, Dec. 24, 2018. Heidi Fang Las Vegas Review-Journal @HeidiFang

The Raiders have officially cut ties with Oakland after declining their option to play the 2020 season at the Oakland Alameda Coliseum, according to a source close to the team.

They are set to begin next season at Allegiant Stadium, their new $1.9 billion home in Las Vegas.

The Raiders had 45 days from the end of last season to notify Bay Area officials whether they would need to exercise the clause — the safeguard was negotiated into the final lease the club signed in Oakland in the event of some unforeseen circumstances compromising construction of Allegiant Stadium — and they informed officials weeks ago they were declining.

The recent mandate by the state of Nevada to close non-essential businesses has not affected work on Allegiant Stadium. Construction remains on pace for the targeted opening.

Contact Vincent Bonsignore at vbonsignore@reviewjournal.com.Follow @VinnyBonsignore onTwitter.