Mr Farage said a "clean Brexit" could allow Britain to put an end to "massive" European Union tariffs stopping African countries from "trading their way out of poverty."
The Common Customs Tariff (CCT) is in place in all member states on goods entering the country from outside the EU – with duty rates varying based on the nature of the trade products.
The staunch Brexiteer said: "We give money to poor countries in the third world. We do so to assuage our consciences. We do so because we certainly wouldn’t want to let the public know the truth about the way we actually treat these countries.
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"The biggest culprit of all of this in the world is the European Union. This protectionist club who, through their common external tariff, make it very difficult for those countries to sell us goods. Why? Because we put massive tariffs on them through the common external tariff.
"If you really want to help the third world, if you really want to help black Africa, back clean Brexit campaign so that we as a country can reduce those barriers and enable those countries to start to trade their way out of poverty."
Last week a Daily Express petition signed by 100,000 readers was presented to Prime Minister Theresa May demanding the British Government cut the foreign aid budget.
The crusade urged Mrs May to cut Britain’s foreign aid budget so more money can be spent in the UK on the NHS and to pay for social care for the elderly.
More than £13billion of taxpayers’ money was spent last year while the Government struggles to fund health and social care funding at home
Speaking on his daily LBC show, Mr Farage said: "Trade, not aid is a way of guaranteeing genuine economic growth and some hope for those countries.