Mercury One 2 One wants to put up an 80ft lattice mast at the entrance to Wootton, a beauty spot on the River Glyme two miles from Blenheim Palace at Woodstock. It would have six antennae and four microwave dishes. More could be added if other phone companies leased space.
Locals say the mast would ruin the view of Wootton, which has been voted Oxfordshire's best-kept village four times.
Mercury has negotiated a long-term lease with the duke for the site, subject to planning permission. It would be a highly profitable arrangement for the duke, whose recent money-spinning ventures include renting out Blenheim to Kenneth Branagh for the filming of Hamlet and hosting the wedding reception of Sylvester Stallone.
The Campaign for the Protection of Rural England is alarmed at the proliferation of cellphone masts, new rural eye-sores in the 1990s. Eight thousand have already been put up and 4,000 more are planned by 2000 as companies invest upwards of pounds 1bn. One 2 One, launched in 1992, already covers 80 per cent of the country.
The duke's agent, Philip Everett, said: "We're leaving it to the local authority to decide on its visual effects. But the site has our blessing for a transmitter if they get planning consent."
Ben Brooks, farmer and parish council chairman, said the mast would destroy trees. "These transmitters are some of the ugliest structures in the countryside," he said. "To think of putting one up at the entrance to a conservation village is monstrous."
A One 2 One spokesman said: "We were looking for a site which was well screened and I think we've found it."