The Serious Fraud Office is investigating donations made to the Labour Party in 2017.

The SFO is presently conducting four investigations in relation to electoral funding matters.

A fifth matter that the agency investigated relating to electoral funding is now before the courts.

"We consider that making the current announcement is consistent with our past practice in this area of electoral investigations and in the public interest," says SFO director Julie Read.

In the interests of transparency and consistency, the SFO has announced the commencement of all these investigations, but has no further comment to make.