U.S., Canadian and European telecom stocks were among the ​top decliners on their respective benchmarks on Friday ‌after SpaceX’s SPCX-Q acquisition of low-band spectrum heightened concerns over growing competition from satellite-based mobile services.

With the deal, SpaceX aims to allow Starlink Mobile to bypass conventional cell towers where ⁠possible, and ​compete with the big wireless carriers on both broad coverage and reliable indoor service, potentially positioning satellite connectivity as a mainstream alternative to traditional cellular networks.

T-Mobile US TMUS-Q slid 9.1 per cent to its lowest level in over 33 months, AT&T dropped ​T-N 7.4 per cent and Verizon VZ-N lost 5.9 per cent, with those two stocks hitting ‌their lowest in over two months.

All three were the biggest percentage decliners on the S&P 500 in early trading.

In sympathy with the U.S. move, the TSX telecom index was down 4.5%. BCE was down nearly 5% at midday.

“The implications for AT&T, T-Mobile, and Verizon are somewhat negative: their defenses against low-band spectrum claims are weakening,” said Kutgun Maral, media, cable & telecom equity research analyst at ‌Evercore ISI.

In ​Europe, Deutsche Telekom, the ‌largest telecom operator in the region by market value, fell 7.1 per cent, France’s Orange ​lost 1.8 per cent and Spain’s Telefonica slipped 3.3 per cent.

The pan-continental STOXX ⁠600 Telecommunications index dropped over 2.4 per cent to its lowest level since ⁠Jan. 30.

Shares in Airtel Africa, Vodafone and BT Group were the biggest losers on London’s FTSE 100 ​index, falling between 1.7 per cent and 4.3 per cent.

The slide came after reports that SpaceX had agreed to acquire private-equity firm Grain Management’s nationwide 800 MHz spectrum portfolio in a deal valued at about US$8-billion, bolstering the company’s ambitions in satellite-to-cellular connectivity.

“This strategic shift places SpaceX in a stronger negotiating ⁠position and highlights an evolving competitive landscape in the telecom sector, reminding investors of the parallel trends seen in fixed wireless services over the last decade,” added Maral.

Low-band spectrum can travel longer distances and penetrate buildings and other obstacles more effectively than higher-frequency airwaves, enabling SpaceX’s Starlink Mobile push.

While the companies did not share financial terms of the deal, the Wall Street Journal reported, citing sources, that it is worth US$8-billion.

SpaceX shares rose 2.2 per cent after announcing the acquisition, which remains subject to regulatory approval.

Towers buck selloff

Telecom tower operators bucked the sector-wide selloff, as investors bet SpaceX’s wireless ambitions could ultimately drive demand for additional terrestrial infrastructure.

American Tower AMT-N, Crown Castle CCI-N and SBA Communications SBAC-Q advanced between 7.6 per cent and 12.6 per cent.

Morgan Stanley said the transaction was “incrementally constructive” for tower operators, noting that even a satellite-centric network could require deployments of towers, rooftops and small cells, while broader urban competition would require substantially more terrestrial infrastructure and spectrum.

With files from Globe staff