By Shivansh Tiwary and Mike Stone

April 23 (Reuters) - U.S. weapons maker Lockheed Martin ( LMT )

beat Wall Street expectations for first-quarter sales

and profit on Tuesday, as simmering geopolitical tensions

prompted some countries to boost their defense spending, driving

demand for new weapons.

Shares of the company, which is considered a bellwether for

the arms sector, rose nearly 2% in premarket trading.

Sales in Lockheed's missiles and fire control unit jumped

25.3% to nearly $3 billion, boosted by strong demand for high

mobility artillery rocket system (HIMARS) and guided multiple

launch rocket system (GMLRS), key weapons used by Ukraine in its

conflict with Russia.

Sales in the company's aeronautics business, its biggest

unit and which makes the F-35 fighter jets, rose 9.2% to $6.85

billion.

"These first-quarter results reinforce our confidence in our

ability to achieve the full-year financial expectations we set

in January," CEO Jim Taiclet said in a statement.

It had forecast full-year net sales of $68.5 billion to $70

billion and a profit of $25.65 and $26.35 per share.

It started the year with a quarterly profit of $6.39 per

share, which was well above analysts' expectations of $5.83 per

share, according to LSEG data.

Lockheed's first-quarter net sales rose 14% to $17.2

billion, also beating analysts' expectations of $16.02 billion.

Last week, the U.S. Missile Defense Agency said Lockheed won

a $17 billion contract to develop the next generation of

interceptors to defend the United States against an

intercontinental ballistic missile attack.

Rivals Northrop Grumman ( NOC ) and General Dynamics ( GD )

are due to report quarterly results later this week.

(Reporting by Pratyush Thakur and Shivansh Tiwary in Bengaluru;

Editing by Anil D'Silva and Savio D'Souza)