When Sir Robert Peel offered Gladstone the vice-presidency of the Board of Trade in 1841, Gladstone complained that while “the science of politics deals with the government of men, I am set to govern packages”.

If Gladstone were alive today, I suspect that he would not hold a similar view. Trade is once again near the top of the political agenda.

Seven years after the Doha Declaration, talks continue at the World Trade Organisation (WTO) in Geneva. The need for a successful conclusion has never been more urgent and the Director-General of the WTO, Pascal Lamy, has called a meeting of ministers on July 21 for what may be the last throw of the dice.

Negotiations focus mainly on agricultural and industrial goods, with potential progress in the liberalisation of commercial services, anti-dumping regulations and fishing subsidies. The main issues centre on the proposed reduction by developed countries of subsidies and levels of protection enjoyed by their farmers, in exchange for freer access to developing country markets for their industrial goods and services.

The WTO operates, however, on the principle of “a single undertaking” by which nothing is agreed until everything is. But there are clear signs of fatigue in Geneva, putting all the progress made to date at risk. Reaching agreement on the Uruguay Round in the early 1990s was similarly protracted but most experts agree that it helped to create millions of jobs and increased world income by hundreds of billions of dollars. We must not risk failure in Geneva - ministers should redouble their efforts to reach agreement when they meet later this month.

At a time of growing financial uncertainty, the trading system established by the WTO provides an important source of economic stability for governments, business and consumers.

It is vital that international trade in goods and services keep flowing. In 1930 the Smoot-Hawley Tariff Act helped to turn a stock market crash into a large-scale depression as sharply increased US tariffs provoked retaliation around the world. Only in 1945, with the end of the Second World War, was there a determined international attempt to reopen markets. Erecting new tariff barriers now would do little to protect jobs and improve living standards.

The worldwide escalation in food prices in recent months has badly hit developing countries that are net food buyers or rely on imports. Completion of the Doha Round would help to mitigate the impact of high prices by tackling systemic distortions in the international market for food, in particular by lowering barriers to trade in agricultural products and by reducing subsidies in many developed countries.

If agreement is not reached in the coming weeks, the talks may collapse with little prospect of revival. In January there will be a new Administration in Washington and a new EU Trade Commissioner in Brussels. This could lead to a further period of review when the need to conclude this round is becoming more critical by the day.

There is a danger that, if this round fails, the future of the multilateral trade system itself will be at risk. Countries could revert to more restrictive policies, shutting out others to the detriment of the global economy. The multilateral trading system embodied in the WTO has contributed significantly to economic growth and employment throughout the past 50 years and must continue to do so.

Along with the benefits of increased trade there are, of course, some dislocations. They are a legitimate source of concern and justify remedial action, both in the context of future agreements and in reaction to their effects. But the answer is not to reduce or restrict trade.

The proper response is to expand and increase trade, reaping its many benefits, while making appropriate adjustments to remedy the dislocations of the past and to minimise them in the future.

Finally, there is a moral dimension to trade. Because it is based on mutual need and the ability of each party to make the other better off, trade, unlike aid, confers dignity and self-respect to both sides of the exchange.

In 1817 the British economist David Ricardo demonstrated how poor countries can become richer by trading with wealthy ones. Ricardo's view was essentially optimistic - that economic interchange between people has the potential to improve the human condition and relations between countries. This can bring hope of a better future to the poor - and can benefit developed nations.

During my time in the US Senate I was closely involved in the establishment of both Nafta and the WTO. I know first hand how difficult it can be to reach agreement between so many parties and such diverse interests. In light of the global economic slowdown, however, it is essential that we maintain policies that encourage free and fair trade, thus promoting recovery, growth and economic development.

Agreement is a prize worth fighting for - ministers cannot afford to fail.

Senator George Mitchell is chairman of the law firm DLA Piper; from 1989 to 1995 he was Democratic leader of the US Senate

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