From Mr Robert McGee and Prof Yeomin Yoon.

Sir, Robert Wade's call for the Obama administration to “[affirm] the right of payments-constrained developing countries to make much more use of safeguard provisions ... of the General Agreement on Tariffs and Trade” (“Time for more subtlety in world trade”, Letters, June 29) has some merit in that it may provide passive and temporary assistance for certain developing countries with very limited foreign exchange reserves. However, it would not provide any positive and sustainable assistance for developing countries that badly need to increase hard currency earnings by exporting their products to such developed countries as the US.