The Scottish Police Authority and Police Scotland have been hit with fresh criticism for failing to tackle budget pressures.

Auditor general Caroline Gardner said it was "unacceptable" she had to draw attention to concerns about financial leadership for the third year in a row.

Ms Gardner said her annual audit of the Scottish Police Authority (SPA) highlighted policing in Scotland continued to struggle under "considerable budget pressures".

The audit uncovered inaccurate records and poor financial management.

Ms Gardner's report, laid before the Scottish Parliament on Thursday, said "significant corrections" had to be made to SPA's accounts.

It outlined that in 2015/16, the SPA had a total spend of £1.1bn, including the use of reform funding from the Scottish Government.

The auditor concluded that while the accounts featured more detail on what reform funding was being used for, a further breakdown was still needed for spending on areas including property, plant and equipment.

"In my opinion, adequate accounting records have not been kept in respect of these areas for the 2015/2016 financial year," she wrote.

The report said the SPA needed to be generally more open about how it allocated funding to Police Scotland and what each investment was expected to achieve.

Ms Gardner said the authority provided "very limited publicly available detail" about its budget for Police Scotland, "impeding effective scrutiny and transparency to the public".

She also called on the SPA to continually revise its long-term financial strategy to help keep its accounts in check.

The report estimated the SPA and Police Scotland could face a cumulative funding gap of almost £190m by 2020/21.

At the end of 2015/2016, there was a £20.5m overspend on revenue budget and a £19.4m underspend on the capital budget.

In an "exceptional" move last month, the Scottish Government agreed for the underspend to be offset against the overspend.

Ms Gardner said: "The Scottish Police Authority and Police Scotland are among the largest and most important public bodies in the country.

"It's therefore unacceptable that I've had to report to the parliament on weak financial leadership and management in all three years of their existence."

She said good leadership was needed to weather the challenges of emerging threats such as terrorism, community safety and local policing.

"Substantial improvement is required now to deliver the strong financial leadership, long-term planning and robust scrutiny that will be needed if policing in Scotland is to withstand the major challenges ahead," she added.

Andrew Flanagan, chairman of the SPA, said: "I remain confident that the savings target expected of police reform by 2026 will be delivered.

"In the new year we will publish a strategy for policing over the next decade that will focus on service to the public and not simply savings.

"It will be underpinned by a long term financial strategy to ensure the service is sustainable in the face of rising demand of increasing complexity."

Mr Flanagan acknowledged Audit Scotland's report and said there was "undoubtedly still more work that needs to be done" to address the concerns.

He added: "Over the last nine months a number of significant improvements have been announced and implemented to strengthen financial management of policing.

"I am confident that the new arrangements translate to a step-change in policing's approach to financial planning and control and will help address more fully the issues Audit Scotland raise within the current financial year."

John Foley, chief executive of the SPA, said 2015/16 was a "challenging year" but pointed to the "significant" scale of savings already achieved.

He added: "There are issues raised by Audit Scotland regarding capabilities and accounting for fixed assets during the year which I am personally working with Police Scotland's Executive to ensure are urgently addressed.

"In addition to the financial management changes already under way, we will invest in ensuring the finance function has the appropriate capabilities required."

Police Scotland's deputy chief officer, David Page, said: "Police Scotland is committed to ensuring our financial management of the police budget is of the highest standard.

"We will continue to work with the authority to ensure the appropriate resources are in place to improve capacity and capability to address the issues raised by Audit Scotland in their report."

The audit was published on the same day as a report by HM Chief Inspector of Constabulary in Scotland, Derek Penman.

He also highlighted the "major financial challenges" facing Police Scotland and the SPA.

"Although there have been changes in the strategic financial leadership of both Police Scotland and the SPA, urgent work is still needed to strengthen their finance function and improve their scrutiny governance," he wrote.

Mr Penman raised concerns about using capital to offset deficiencies in the revenue budget, saying it was "neither desirable nor sustainable".

He added: "[It] significantly curtails the essential strategic investment in estates, vehicles and ICT enabled change that underpin transformation."

The auditor general will report again on the progress of the SPA and Police Scotland next year.