April 24 (Reuters) - Electronic equipment maker Amphenol beat market expectations for first-quarter revenue on Wednesday and announced a new $2 billion share buyback program, sending the company's shares up as much as 4% in premarket trading.

Heightened geopolitical tensions in the Middle East and the ongoing Russia-Ukraine war have boosted demand for Amphenol's connectors and sensor systems that are used in defense systems.

"Sales increased from prior year by 9%, driven by growth in the IT datacom, commercial air, automotive and defense markets", said Amphenol CEO R. Adam Norwitt.

Amphenol also said it has launched a three-year $2 billion open market stock repurchase program.

The company reported revenue of $3.26 billion in the first quarter, beating analysts' average estimate of $3.10 billion.

It forecast second-quarter revenue in a range of $3.24 billion to $3.30 billion compared with expectations of $3.26 billion, according to LSEG data.

Amphenol reported earnings per share of 87 cents per share, compared with 71 cents per share, a year ago.

Revenue for the company's communications solutions unit, its largest division by sales rose around 12% to $1.27 billion.

Amphenol has been on an acquisition spree, having closed four acquisitions in its fourth quarter.

The Wallingford, Connecticut-based company recently acquiring Carlisle Interconnect Technologies in January, a unit of Carlisle Companies for about $2 billion in cash, which supplies cables and connectors to defense and industrial end markets. (Reporting by Zaheer Kachwala in Bengaluru; Editing by Tasim Zahid)