By Adwitiya Srivastava and Nikita Maria Jino

(Reuters) - Shares of Reliance Worldwide Corporation were on track for their weakest session in about a month, after the Australian firm warned of pressure on 2025 Americas sales and cut its earnings outlook as it braces for the impact of U.S. tariffs.

Shares in the plumbing solutions provider slumped as much as 4.1% on Monday, their largest intraday fall since April 9, while the broader benchmark index traded 0.7% lower.

The company said it would now shift product sourcing from China to alternative locations including Vietnam, Taiwan, Thailand, and its own facilities in the U.S., U.K., and Australia.

It also flagged a total cost impact of up to $35 million on its operating earnings for the next fiscal year.

The firm's downbeat guidance joins a growing list of big-cap companies which are either scrapping or cutting their 2025 guidance, offering fresh evidence that U.S. President Donald Trump's unpredictable trade moves were making it increasingly difficult for businesses to plan beyond the short term.

Reliance Worldwide said nearly half of its cost of goods sold in the Americas region comes from outside the U.S. —including raw materials, components, and finished products —making it potentially vulnerable to tariffs.

Analysts at Citi called Reliance Worldwide's outlook shift "conservative", with the impact on fiscal 2026 earnings to only be sustained if tariffs on China remain in place for the duration of this year.

The group currently generates around 70% of external revenue from its Americas business, as per its 2024 annual report. (This story has been refiled to remove extraneous words after paragraph 1)

(Reporting by Adwitiya Srivastava and Nikita Maria Jino in Bengaluru; Editing by Kim Coghill, Himani Sarkar and Rashmi Aich)