Chancellor George Osborne will deliver the message in Edinburgh, which will be swiftly endorsed by Labour and the Liberal Democrats.
Mr Osborne will say he wants Scotland to keep its “economic security”.
Deputy Scottish First Minister Nicola Sturgeon said Westminster was trying to “lay down the law to Scotland”.
The Scottish government wants to keep the pound in a currency union if there is a Scottish independence “Yes” vote on 18 September.
“The pound is one of the oldest and most successful currencies in the world,” Mr Osborne will say.
“I want Scotland to keep the pound and the economic security that it brings.”
“The UK works in good times and also in bad.”