Michael Spicer condemned Brussels for its lack of a relationship between the electorate and government.
Even though countries send elected representatives to the European Parliament, the European Commission, which is effectively the trading bloc’s government, is made up of appointees from the 28 member states – a fact alluded to by the Brussels arch-critic.
Lord Spicer told the Telegraph: “Nowhere in the constitution of the EU is there a direct relationship between the electorate and the government.
“The EU therefore is not democratic. It shares this feature with China and Russia.”
He said leaving the EU would therefore restore “the key element of democracy”.
He added: “This central point was effectively recognised at the British referendum. Any reversal of this would be to deny the legitimacy of the referendum.”
Officially, China is a multi-party socialist state, but in practice the membership of the government is largely determined by the Communist Party of China.
Russian politics is heavily dominated by Vladimir Putin’s United Russia party, with widespread irregularities identified by independent observers in the presidential election of 2012, in which he picked up 63.64 per cent of the vote.
Rumours of corruption persist, and Mr Putin himself wields enormous influence over political appointments.
Once the details of the legislation setting out how Britain will withdraw from the EU have been agreed, it will need to be ratified by parliament before it becomes law.
All this must be achieved within tight time frame, with the date already fixed for March 29, 2019.
Lord Spicer predicted trade matters would have comparatively little influence on MPs when they came to make their minds up about the legislation.
He explained: “If the European Union were simply a trade area, a ‘common market’, I cannot think of any reason why we would wish to leave it.
“But the EU is not merely a common market. In it’s very constitution it is defined as an ever closer union.”
Lord Spicer launched the European Research Group (ERG) in 1993 when he was chair of the Parliamentary Office of Science and Technology, to reflect the views of Conservative MPs who were becoming increasingly concerned at what they saw as the trading bloc’s federal tendencies.
The group currently boasts a membership of 50 backbench Conservative MPs.
Lord Spicer hit the headlines last year when he suggested to Brexit Minister Baroness Anelay that, rather than having to foot a hefty divorce bill, the EU could end up owing the UK money.
He said: “When does my noble friend expect the valuation of EU assets to be completed?
“Is it not the case that if proper account is taken of the assets, that we could even end up with the EU paying us rather than the other way around.
“You first heard the idea here.”