DUP MP Ian Paisley Jnr may have had his phone hacked by News of the World reporters.
It is believed the police are investigating whether Mr Paisley's calls were intercepted around 2007 when he was a Stormont MLA.
When contacted by the BBC, the MP said he would not be making any statement.
The Metropolitan Police said they were not prepared to discuss who may or may not be involved in the ongoing investigation.
Mr Paisley was elected to Westminster in the 2010 general election when he succeeded his father in winning the North Antrim seat.
In anonther development, the News of the World's owner has said sorry over the scandal which saw celebrities' and politicians' mobile phones hacked by the paper's journalists
News International is to set up a compensation fund.
The company says, in some cases, it will apologise and admit liability.
The BBC understands it hopes to pay out less than £20m in total to victims, including actress Sienna Miller.