The US Strategic Command unit has apologized for a tweet that was sent in "poor taste."

The tweet, which has since been deleted, claimed the unit was ready to drop something "much, much bigger" than New York's New Year's Eve ball.

Footage of an aircraft releasing bombs accompanied the tweet.

The arm of the US military that controls the launch of nuclear weapons tweeted that it was ready to drop something "much, much bigger" than New York’s New Year’s Eve ball.

Alongside the message, which has since been deleted from the social media site, the US Strategic Command unit shared footage of an aircraft releasing bombs.

The tweet came just hours before 2019 was welcomed at midnight during the famous annual ball in New York’s Time Square on Monday night.

After deleting the message, the command unit apologised, admitting that the tweet was in "poor taste."

The deleted message read: "Times Square tradition rings in the New Year by dropping the big ball… if ever needed, we are ready to drop something much, much bigger."

—US Strategic Command (@US_Stratcom) December 31, 2018

The accompanying video showed a B-2 bomber dropping bombs, followed by explosions on the ground.

Later on Monday, the message was deleted. A new message said: "Our previous NYE tweet was in poor taste and does not reflect our values. We apologize. We are dedicated to the security of America and allies."