In January 1950 Gaitskell submitted a paper called "Control and Liberalisation" to the Economic Policy Committee, which he was sometimes invited to attend. He wrote that "On 'liberalisation' we have gone about far enough. But we have done it for political reasons – US and Europe". He was opposed to the convertibility of currencies and non-discrimination between trading partners, both policies which the USA favoured. Britain still preferred to encourage trade in pounds sterling within the Commonwealth, and Gaitskell wanted to preserve Britain's ability to avoid downturns like the US downturn of 1948–9, which Britain had largely escaped because of devaluation.