Ambulance dispatch times for critical 999 calls in the north and north-east of Scotland have spiralled over the last three years.
Shock new figures show it took just under 50 seconds to send out Grampian paramedics to the most serious incidents in 2013/14, compared with more than a minute and 20 seconds this year.
In Highland, the time it takes for ambulances to be assigned to Category A jobs has risen by 52% in the same period.
Opposition politicians have said the increasing delays could be the difference between life and death for critical patients, particularly in rural areas.
Earlier this year, the Press and Journal revealed that mercy crews in Grampian have failed to hit response targets for life-threatening emergencies for three years running.
Scottish Ambulance Service (SAS) CEO Pauline Howie said there was a “challenging context” but that response times were improving.
Scottish Conservative community safety spokesman Oliver Mundell MSP said: “It’s clear from these figures that there’s been a major slip in performance with response times.
“They’ve got consistently worse, and this has to change as a matter of urgency.
“For every second that someone has to wait longer for an ambulance, their chances of recovery can worsen.”
In 2013/14, it took 48 seconds from a Grampian 999 call being received to an ambulance being dispatched. This year it took one minute and 23 seconds.
It took 58 seconds for an ambulance to be assigned following a 999 call in Highland in 2013/14 – but now takes one minute 32 seconds.
Mr Mundell added: “I appreciate measures have been put in place to address this, but people will be sceptical about their impact.
“The Scottish Ambulance Service doesn’t have its problems to seek, especially in rural areas.
“The SNP has been in charge of this for almost a decade, and has to take full responsibility for these delays.”
SAS’ Ms Howie said the number of Category A incidents had increased by 4% since last year.
She added: “Despite the challenging context of increased demand for services, the average response time for potentially life threatening calls was 7.4 minutes in Scotland and we reached more Category A Cardiac Arrest patients within 8 minutes than the previous year, up by 4.5%, again, saving more lives and improving patient outcomes.”