The Electoral Commission has confirmed there are “reasonable grounds to suspect an offence or offences may have occurred” relating to works at the Prime Minister’s home at 11 Downing Street.
The announcement comes just before Boris Johnson appears at Prime Minister’s Questions for the first time since former aide Dominic Cummings accused him of wanting donors to “secretly pay” for the renovations in a “possibly illegal move”.
In a dramatic twist, the political spending watchdog said it will launch a formal investigation to establish whether an offence has been committed.
An Electoral Commission spokesman said: “We have been in contact with the Conservative Party since late March and have conducted an assessment of the information they have provided to us.
“We are now satisfied that there are reasonable grounds to suspect that an offence or offences may have occurred.
“We will therefore continue this work as a formal investigation to establish whether this is the case.
“The investigation will determine whether any transactions relating to the works at 11 Downing Street fall within the regime regulated by the Commission and whether such funding was reported as required.
“We will provide an update once the investigation is complete. We will not be commenting further at this point.”