The Cabinet Office has not published data on how quickly it paid its suppliers for 12 months in 2017 and 2018 due to a computer system issue.
The problem emerged in response to a question asked by Labour shadow cabinet office minister John Trickett as to where payment data from April 2017 onwards was.
Cabinet Office minister David Lidington said the move to a new platform in May 2017 had caused problems with transferring payment performance data.
The department was forced to suspend its prompt payment reporting as a result until it was sure of the data again.
“This has now been achieved, and we plan to publish the outstanding data shortly,” Mr Lidington added in his response at the start of November.
On 19 December, the Cabinet Office’s prompt payment performance data was updated, but only with six months of figures covering April 2018 to September 2018.
Those figures show the government’s performance had worsened by almost ten percentage points.
And the department has still not published date for the 12 months from April 2017 to March 2018.
Mr Trickett told Construction News the failure made it hard to have confidence that the government was serious about tackling prompt payment problems.
“The government constantly talks about the need to reform procurement, but they can’t even get their own house in order,” he said.
“Late payment is a big issue for public sector suppliers and subcontractors, and this will give them absolutely no confidence that the government intends to fix it.”
FMB chief executive Brian Berry echoed Mr Trickett’s concerns.
He said: “The fact that the Cabinet Office hasn’t published any data on how promptly it has paid its own suppliers for a full year is disappointing and calls into question how serious the government is about ending poor payment practices.
“The government must lead by example and be completely transparent.”
NFB chief executive Richard Beresford also called on the government to improve its reporting urgently.
He said: “The government has a real opportunity to lead by example and so it is vital it publishes its prompt payment performance data, for the benefit of the whole supply chain.
“The industry needs to know that late payment doesn’t pay.”
The new data that was published covering April to September 2018 showed the government’s prompt payment performance has worsened.
Over the six months an average of 89.5 per cent of invoices were paid within 30 days, almost 10 percentage points lower than the average of 98.2 per cent for the same period in 2016 when the data was last published.
Prompt payment moved up the government’s agenda in 2018 following the collapse of Carillion, one of its largest suppliers.
In November, minister for implementation Oliver Dowden warned firms on government jobs that from autumn 2019 they would have to demonstrate they were paying suppliers on time. Those that failed to could be blocked from winning future contracts.
The Cabinet Office has been contacted for comment.