Our Politics newsletter is now daily. Join thousands of others and get the latest Scottish politics news sent straight to your inbox. Subscribe Thank you for subscribing We have more newsletters Show me See our privacy notice Invalid Email

DAVID Cameron is pressing ahead with plans to force an independence referendum ahead of Alex Salmond’s 2014 poll.

In a move that will add to tension between Westminster and Holyrood, the PM plans to amend the Scotland Bill to force the SNP to ask the “in or out” question within 18 months of the Bill being passed.

Scotland Office Ministers in Whitehall are frustrated over the lack of progress at two negotiation meetings with Salmond this month and are now ready to step up the argument for a one-question referendum “sooner rather than later”.

According to a timetable set out by the Scotland Office, an indy poll could be held in 2013.

Scotland Office Minister David Mundell insisted last night that they would not be the first to blink in the constitutional stand-off.

He said: “We can’t back down. We would rather agree the referendum through conciliation but if that doesn’t work in the short term, then we have to keep all options open.”

Cameron has offered to transfer powers to hold a constitutional referendum to Holyrood to prevent the issue being delayed in the courts by a legal challenge.

But in return for new powers for Holyrood, he wants a single-question poll instead of Salmond’s multi-option preference.