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.
Ukip has accused the Conservative Party of "distracting" from its own spending on Britain's defences in its personal attack on Ed Miliband over Trident.
Ukip's economic spokesperson Patrick O'Flynn said Michael Fallon's claim today that the Labour leader "stabbed his brother in the back" in 2010 was a bid to "distract from the fact that the Conservatives are not pledging to fully resource our armed forces."
"They're not meeting the Nato 2% commitment," he added during a policy briefing in London. "Of course we would commit totally to upgrading Trident - we can afford to do so."
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?