A report by the US Department of Homeland Security claims that President Donald Trump’s wall along the border with Mexico would cost up to $21.6bn and take more than three years to build.
Mr Trump had cited a figure of around $12bn during his campaign for the wall, which Homeland Security said would be made up of fences and walls covering more than 2,000 km by the end of 2020.
The internal report seen by Reuters today is expected to be given to the secretary of the Department of Homeland Security (DHS), John Kelly, in the coming days.
There is already 1,046 km of the border already fortified, and the new construction would be carried out in three phases to extend almost the length of the entire border.
A spokeswoman for the DHS said they "do not comment on or confirm the potential existence of pre-decisional, deliberative documents", while a White House spokeswoman said it would be “premature” to comment on the report which has not officially been presented to the president.
The report also shows that the government has started to seek waivers on environmental laws for building in some areas.