Facebook has introduced new measures that will force political advertisers in the UK to be more transparent about their location and identity in a bid to hold them to account and combat foreign interference in elections.

Advertisers will also have to declare who has paid for their politicals ads before they can gain approval to publish them on both Facebook and Instagram.

According to the company, ads related to politics will be held in an “Ad Library” for seven years to allow for future analysis of their claims.

The system was first introduced in October but a delay in it taking full effect was triggered after journalists were able to undermine it by posing as politicians and a banned organisation.

Adverts said to be from US senators and election consultants Cambridge Analytica, banned by Facebook after a data scandal, were approved by the social network despite being placed by journalists in the UK and US.

Facebook said it had already made changes and was continuing to work on improving its systems.