TUCSON, Ariz. (AP) - Minuteman border watch leader Chris Simcox has a message for President Bush: Build new security fencing along the border with Mexico or private citizens will.

Simcox said Wednesday that he's sending an ultimatum to the president, through the media, of course - ``You can't get through to the president any other way'' - to deploy military reserves and the National Guard to the Arizona border by May 25.

Or, Simcox said, by the Memorial Day weekend Minuteman Civil Defense Corps volunteers and supporters will break ground to start erecting fencing privately.

``We have had landowners approach,'' Simcox said in an interview. ``We've been working on this idea for a while. We're going to show the federal government how easy it is to build these security fences, how inexpensively they can be built when built by private people and free enterprise.''

Simcox said a half-dozen landowners along the Arizona-Mexico border have said they will allow fencing to be placed on their borderlands, and others in California, Texas and New Mexico have agreed to do so as well.

``Certainly, as with everything else, we're only able to cover a small portion of the border,'' Simcox said. ``The state and federal government have bought up most of the land around the border. I suspect that's why we'll never get control of the border.''

But he said the plan is to put up secure fencing that truly will be an effective deterrent, and to show how easily it can be accomplished.

Simcox gave this description of the envisioned barrier-and-fencing complex:

Start with a 6-foot deep trench so a vehicle can't crash through; behind it, roll of concertina (coiled, razor-edged barbed wire), in front of a 15-foot high heavy-gauge steel mesh fence angled outward at the top.

Behind the fence will be a 60- to 70-foot wide unpaved but graded dirt road, along with inexpensive, mounted video cameras that can be monitored from home computers. On the other side of the road will be a second, 15-foot fence, with more concertina wire on its outside.

``It's a very simple, effective design based on feedback we've had from Border Patrol and the military,'' Simcox said. ``It's a fence that can be built on the cheap, effective and secure.''

Simcox said supporters will try to build the fencing with volunteer labor. Surveyors and contractors have offered to help with the design and survey work, he said, and some have said they will provide heavy equipment.

Simcox said those involved in the planning hope to keep costs to between $125 and $150 a foot.

Access to land literally on the border is an issue because so much is state-leased trust property or federally owned, he said.

``You may have to deal with a situation where private property owners erect their own fences and may be faced with the president sending the National Guard to prevent them from protecting their private property,'' Simcox said.

He said the Minuteman plan is ``to keep turning up the heat'' until President Bush has to respond somehow.