Dr Jack Cunningham, the "cabinet enforcer", will tell a meeting in his Copeland constituency the House of Lords is less democratic than Cuba, China and Albania.

The only system equivalent to Parliament's upper chamber is used by tribal chiefs in Zimbabwe, according to Dr Cunningham.

Dr Cunningham: Hereditary peers make democracy a "laughing stock"

He says: "In no other major democracy anywhere in the world does your parentage put you into parliament.

"In no other parliamentary chamber does the hereditary principle give you the key to passing laws which will govern the lives of others."

Dr Cunningham's staff searched for anywhere in the world where the hereditary principle applied.

He says: "We think we may have found an example. Just one. Where tribal chiefs in Zimbabwe form what is called a 'functional constituency' which is represented in the second chamber.

"We're not sure. We're checking. But we think that may be it."

The Lords have spent two days discussing Labour's plans to remove hereditary peers' right to speak and vote, which were introduced by Baroness Jay on Tuesday.

She announced a Royal Commission to establish to look into the reforms and the future composition of a second chamber.

Dr Cunningham says: "The hereditary peers in the House of Lords make a laughing stock of democracy.

"Cuba is democratising. China is democratising. Albania is democratising.

Dr Liam Fox: Labour wants a neutered chamber

"But the Tories and the hereditary peers? No."

Labour's step-by-step proposals to reform the Lords have been condemned by the Conservatives who want the process carried out in one go, while some peers have said they will act like football hooligans to prevent reform.

Conservative spokesman for Constitutional Affairs, Dr Liam Fox, condemned Mr Cunningham's speech as "political venom" without any serious proposals for reform.

He said: "Don't be fooled into thinking this is just the first step in a well-thought-out programme of reform.

"Labour see it as their final solution.