An analysis of the Register of Lords’ Interests shows 169 peers reported working as advisers earlier this year, with more than a dozen registering that they were also paid by foreign governments on top of the expenses they are entitled to as peers.

The consultancies range from a former Conservative MP advising the company of a Romanian businessman facing extradition, through to a former chief of defence staff who advises the government of Bahrain.

The worlds of finance, energy, mining and defence are extensively represented among peers’ clients. Unlike MPs, peers are considered part-time public servants, which allows them to pursue other business. Peers are permitted to work as advisers for private interests, as long as they are properly declared.

The findings include:

A leading Labour peer, Lord Levy, has apologised after admitting failing to register three private interests connecting him to a billionaire Russian businessman.

Fifteen peers are working for or advising foreign governments, including a former coalition government cabinet minister and a former chief of defence staff.

Thirty-eight peers indicated they provide public affairs or strategic advice, an area of particular sensitivity because such work can easily stray into lobbying.

Eighty-three peers have declared an interest in finance or banking, with HSBC, Santander and Royal Bank of Scotland among those to have provided paid roles as directors or paid advisers to peers.