The Catholic Institute for International Relations has produced 15,000 postcards to highlight the current problems in Haiti.
The charity hopes that its members and supporters will send the cards to Hilary Benn, the Secretary of State for International Development.
Political unrest in Haiti led to the resignation of President Jean Bertrand Aristide in February and prompted the UN Security Council to send in a multinational military force to restore law and order.
Haiti then fell prey to devastating floods in September, which killed 3,500 people and left thousands more without food.
Anne Street, the charity's advocacy co-ordinator for Latin America and the Caribbean, said: "Haiti is the poorest country in the western hemisphere."