Is it right that more and more greenbelt land in the UK is being built upon for new houses?

We don't need to build on greenbelt land. Hundreds of houses lie empty, bought by foreign investors to be used as profit. Some parts of the UK do not have a housing problem at all, and there are plenty of spare properties. But the areas have become run down and unattractive. These areas should be reinvigorated and made attractive as places to live, or cleared and rebuilt on.