UK's Rightmove property website may be acquired by Rupert Murdoch's group, causing shares to surge 21%.

• REA Group, owned by Rupert Murdoch, is considering a takeover bid for Rightmove to establish a global digital real estate business.
• The Australian property business viewed the potential acquisition as a "transformative opportunity" and highlighted "clear similarities" between the two companies.
• Shares of Rightmove jumped 25% in early deals following the announcement.

Rupert Murdoch-owned News Corp announced on Monday that it is considering a takeover bid for U.K. property portal Rightmove in a bid to establish a global digital real estate business.

News Corp, which controls an Australian property listings company, stated that it is considering a possible cash and share offer for Rightmove, but no discussions have been held yet.

The stock of Rightmove experienced a 25% increase in early deals after the announcement, reaching a 20.9% increase by 12:32 p.m. and remaining at the top of the FTSE 100. On the other hand, REA Group's shares dropped by as much as 6%.

CNBC did not receive a statement from Rightmove and the company did not respond to their request for comment.

According to the Financial Times, REA Group made an announcement following reports that it was collaborating with Deutsche Bank on a significant overseas acquisition.

The U.K.'s leading property portal, Rightmove, is used by estate agents to advertise properties for sale and rent. The Melbourne-headquartered REA Group did not disclose how much it was considering offering for Rightmove, but the U.K. platform was valued at £4.34 billion ($5.7 billion) as of market close Friday.

REA Group viewed the potential acquisition as a "transformative opportunity" due to "clear similarities" between the two companies, such as strong brand awareness, market share, and "highly aligned cultural values."

News Corp, through its subsidiary REA Group, operates a variety of property websites in Australia, India, and the U.S.

During the Global Financial Crisis, REA Group sold its real estate site PropertyFinder Group to Rightmove rival Zoopla in the U.K., facing intense market competition.

The U.K. property market is now more favorable due to lower interest rates, which are expected to increase transactions. However, Rightmove may face challenges following the acquisition of its rival site OnTheMarket by a U.S. property firm.

REA Group, which has previously faced competition from CoStar in the U.S. through its investment in realtor.com, appeared undeterred by increased market competition, according to Jefferies analysts in a note on Monday.

Although there are limited "cross-border synergies" between the two firms, Jefferies analysts believe that Rightmove could benefit from REA's strong management and expertise in Rightmove's "strategic growth areas," such as mortgages, commercial and rental services.

The analysts acknowledged REA's strength in Australia by taking revenue share from DHG, the #2 player in the Australian property portal market, over the past six years.

Under UK takeover laws, REA must make an offer or withdraw by the end of September after expressing interest publicly.