In a major intervention on the furore surrounding local housing plans, the South Staffordshire MP said there needed to be a "complete shift away" from developing on green sites across the region.
He said it was "completely wrong" that South Staffordshire was having to give up land for around 4,000 homes to make up a shortfall from other local authorities, and said not enough was being done to unlock brownfield sites in the Black Country which desperately needed regeneration.
Dozens of green belt sites are under threat in the Black Country for 7,720 homes, while in South Staffordshire land is required for 8,881 homes - nearly half of which are to make up a shortfall from other areas.
It came as Boris Johnson hinted that a move away from green belt development may be on the horizon, with reports suggesting that an overhaul of the country's planning laws may be scrapped.
Former cabinet minister Mr Williamson said he had been lobbying ministers for a "new approach" to development which protects the green belt and focuses on bringing old industrial sites back into use.
He told the Star: "What we need is a much heavier emphasis on brownfield sites as opposed to intruding onto the green belt.
"At the moment we are waiting to see what the new legislation is going to look like, but there are suggestions of a real change in focus.
"One of the key challenges for South Staffordshire is the extra numbers put on in the plan to meet the housing needs of other local councils.
"This is completely wrong, and once those extra homes are removed you get a very different picture. There is a need for housing, but it should never result in the green belt being destroyed.
"In the Black Country there are thousands of acres of brownfield sites that need to be brought back into use for homes. There are wastelands where at the moment, there is neither homes nor jobs.
"Developers will always want to build on the green belt as it is cheaper and easier to do. I would hope that with the new strategy we will see a substantial reduction in the amount of homes that have to be built in South Staffordshire.
"With a careful and considered approach to planning and the right investment, we can protect the green belt.
"This would also bring in much-needed regeneration to parts of the Black Country that would really benefit from new housing."
Under the South Staffordshire Plan, four sites have been earmarked for 4,300 homes. They include 1,200 homes at land off Linthouse Lane and Wood End Road in Essington, and 1,200 homes at Cross Green in Coven.
The West Midlands Combined Authority has this week been awarded up to £33 million in government funding for brownfield redevelopment.
A consultation on the Black Country Plan ends at 5pm on Monday.