The number of people waiting more than six months for inpatient or day case treatment in Scotland's hospitals rose by almost a quarter over the summer.
More people were waiting for hospital treatment
The Information and Statistics Division of NHS Scotland said the figure had grown from 6,161 to 7,512 in the three months to the end of September.
However, it said the number was down by 3,000 on last year's total.
Health Minister Andy Kerr said a pledge that no-one would wait more than six months by the end of 2005 would be met.
The figures for the last quarter showed that no-one with a guarantee waited more than nine months for treatment.
The median wait for inpatients and day cases was 43 days - up two days on last year's figure.
Hospital waiting lists rose by almost 2,000 in Scotland over the last year, with 112,537 people waiting for inpatient or day case treatment on 30 September.
ISD Scotland said the rise may be partly due to efforts to improve the reporting of waiting lists, following a recommendation by Audit Scotland.
The percentage of outpatients seen within 26 weeks of referral fell from 88.3% last year to 87%.
However, this was partly attributed to efforts to target those who had been waiting the longest for treatment.
The length of time people are waiting for an outpatient appointment has not changed over the last year.
For the first time, the statistics also showed the number of outpatients waiting to be seen.
More than 53,000 people were waiting more than six months.
Following the release of the figures, Mr Kerr promised that there would be an unprecedented assault on unacceptable waiting and said the private sector would have a role to play, a move described as a u-turn by opposition parties.
"We are delivering on our guarantees but clearly there is a lot more that needs to be done," he said.
"In my first few weeks as health minister, I learned a great deal about the strengths of the NHS and also its stresses, particularly in outpatients.
"It is my job to sort this out - and that's what I am going to do. I will give further details of this in a major announcement next month.
"We are going to tackle the problems head-on by creating a modernised NHS to serve Scotland for the future."
He said the executive would deliver on a promise of a maximum six-month wait for both outpatient and inpatient/day cases by the end of next year.
'Worse and worse'
The Scottish Conservatives attacked the government's record on health over the past five years.
Health spokesman David Davidson said the latest statistics were "deeply concerning".
He said: "Since 1999, Scotland's health service has officially been getting worse and worse.
"More and more people are waiting longer and longer in ever increasing pain and suffering.
"The Labour/Lib Dem executive has displayed a level of incompetence which few thought possible.
"Money has been thrown into the NHS in Scotland with reckless abandon and a refusal to reform. Scotland deserves much better."