Mobile phones with "Mesh networking" built-in have now started to appear in the market. E.g Tecno Spark Go 3 - https://www.tecno-mobile.com/phones/product-detail/product/s... - recently launched in India has a feature called Freelink 2 that claims to connect with other Tecno phones to provide "connectivity" without wifi or cellular network up to a range of 1.5 kms. More here: https://www.intelregion.com/tech/how-to-use-your-techno-phon... .

(Personally, I don't think any government is going to allow this.)