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STOCKHOLM, April 24 (Reuters) - Swedish home appliances maker Electrolux ELUXb.ST reported on Friday a surprise first-quarter loss as U.S. demand slumped, hours after the company announced a $1 billion rights issue and a tie-up in North America with Chinese rival Midea 000333.SZ.

Electrolux, whose brands also include Frigidaire and AEG, swung to an operating loss of 266 million crowns ($28.7 million) from a year-earlier 452 million profit, blaming a loss in North America due to higher costs for U.S. tariffs and a significant slowdown in demand.

Analysts had on average forecast a 280 million crown profit, according to a poll provided by Electrolux before Thursday evening announcements.

Electrolux said sales in North America, a key region that accounts for around a third of group sales but where it has been struggling for years, shrank organically by 11.6%, leading to a group level drop of 0.5%.

The competitor to Whirlpool WHR.N lowered its North America market outlook for the full year to "negative" from "neutral to negative" due to the U.S. demand slump during the quarter.

It after market close on Thursday announced plans for three joint ventures with Midea within refrigeration and laundry products manufacturing, and a 9 billion crown rights issue to fund the partnership and other restructuring measures.

The partnership and the other separate measures would result in 3,000 job cuts, it said.

CEO Yannick Fierling told analysts and media in a call on Thursday the initiatives would be changing the future of Electrolux long-term.

Electrolux has struggled in the face of weak demand and competition from lower-priced rivals, sending its shares down 75% from 2021 highs. It has been restructuring, cutting costs and focusing on more premium categories in recent years to lift profitability.

($1 = 9.2584 Swedish crowns)