The Conservatives are accusing Ed Miliband of preparing to "stab the United Kingdom in the back", trading away Britain's nuclear deterrent in order to secure power in a backroom deal with the Scottish Nationalists.
The Conservative Party has launched a personal attack on Ed Miliband over Britain's nuclear defense in the run-up to next month's general election.
Tory Defence Secretary Michael Fallon said the Labour leader "stabbed his brother in the back" over the pair's 2010 leadership contest and would do the same to Britain to get into power.
In a speech in London today, Mr Fallon will confirm that the Conservatives plan to go ahead with building four new Trident nuclear missile submarines to replace the existing fleet.
Writing about the UK's nuclear deterrent in The Times (£), Mr Fallon said Mr Miliband would abandon the programme if Labour was given the prospect of forming a coalition with the SNP, which opposes renewing Trident.
Mr Fallon said: "Ed Miliband stabbed his own brother in the back to become Labour leader. Now he is willing to stab the United Kingdom in the back to become prime minister."
He will also accuse the Scottish Nationalists of having a "childlike world view" over security.
The main political parties are wrangling over whether the UK should spend billions renewing its nuclear deterrent.
If a difference of opinion on defence didn't get in the way of the current coalition - why would it be different for Labour and the SNP?