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Feb 23 (Reuters) - Johnson Matthey JMAT.L on Monday agreed to slash the sale price of its catalyst technologies business to Honeywell HON.O by 475 million pounds ($642.49 million) to 1.33 billion pounds, after the unit underperformed in fiscal 2025 with deferred projects and weaker profitability.

The British chemicals company had previously agreed to a 1.8 billion pound deal with Honeywell in May last year as it streamlined its operations to focus on its two main businesses that make pollution filters for cars and process platinum group metals.

Johnson Matthey now expects to return around 1 billion pounds to shareholders following the deal's completion, down from the 1.6 billion pounds in net proceeds originally anticipated.

The companies also extended the deal deadline from February 21 to July 21, with a possible further extension to August 21 if antitrust approvals remain outstanding.

The deal is now expected to complete by August-end.

($1 = 0.7393 pounds)