Lockheed Martin Corp reported quarterly profit below estimates on Tuesday, hurt by lower F-35 deliveries as an economic slowdown brought about by the COVID-19 pandemic dented demand for the US weapons maker's products.

Shares of the company fell 1.2% in premarket trading, after the company said fourth-quarter deliveries of its F-35 jets fell 17.6% from 51 jets a year earlier.

The company said it now expects 2021 revenue between $67.10 billion to $68.50 billion, in line with analysts' expectation of revenue of about $68.04 billion, according to IBES data from Refinitiv.

Lockheed forecast full-year earnings for 2021 to be in the range of $26.00 to $26.30 per share, above analysts' average expectation of $26.13 per share.

Net earnings rose to $1.79 billion, or $6.38 per share, in the fourth quarter ended Dec. 31, from $1.5 billion, or $5.29 per share, a year earlier.

Analysts on average had expected net earnings of $6.41 per share.

Net sales rose 7.3% to $17.03 billion, above estimates of $16.92 billion.