Peace talks aimed at ending the four-year conflict in Darfur will begin in Libya tomorrow as the United Nations and the African Union prepare to deploy a joint force of more than 20,000 troops to the region this year.

But organisers of a divestment campaign that is gaining support in the UK and around the world believe that the solution to the crisis, which has claimed more than 200,000 lives, could lie as much with fund managers as with soldiers and diplomats.

The campaigners are targeting multinational companies operating in Sudan, especially those active in its oil industry, which relies heavily on foreign investment. They argue that the Government has used oil revenues to fund the Janjaweed militia, which has been accused of attacking civilians, forcing 2.5 million people to flee their homes. In addition, they want pension funds and other investors in those companies to engage with them and to divest if they fail to adopt corporate social responsibility policies.

So far, Rolls-Royce, Siemens, ABB of Switzerland and Canada’s CHC Helicopter have announced plans to withdraw from Sudan. Rolls-Royce said that its decision was because of “increasing international humanitarian concerns about the situation in Darfur.” In the US, 18 states, including California and Texas, have passed legislation prohibiting state pension funds from investing in companies doing business in Sudan, according to the Sudan Divestment Task Force, and others plan to introduce similar Bills. Citizens are also being urged to contact a hotline, 1-800GENOCIDE, which will put them in contact with their state governor.

Fifty-four universities, including Harvard and Stanford, have adopted policies restricting investment in Sudan and presidential candidates such as Rudy Giuliani and John Edwards have said that they will divest their Sudan-related holdings. There are also divestment campaigns in Australia, Germany, Italy and South Africa.

After Rolls-Royce’s decision to withdraw, British campaigners, led by Sudan Divestment UK (SDUK) and the Aegis Trust, a genocide-prevention group, are focusing on Weir Group and Petrofac, which provide services to Sudan’s oil industry.

Hamish Falconer, director of SDUK, said that the companies provide valuable expertise, even though their operations in Sudan are small compared with those of other players under scrutiny, such as the Chinese groups Sinopec and Petrochina. “They offer extremely specialist technical assistance which is difficult to find elsewhere,” he said.

Mr Falconer added: “We are trying to get companies to change their behaviour and be a force for change in the country. If these companies, for example, said: ‘We are stopping our operations until we see an end to the genocide, we want to see greater transparency with our oil revenue’, we will leave them be.”

Campaigners have written to Barclays, which according to Aegis Trust holds shares worth about £53 million in Petrofac through Barclays Global Investors and also owns shares worth about £223 million in Petrochina and £108 million in Sinopec.

There are signs that institutional investors in the UK are paying attention to events in the US. A spokesman for Ethical Investment Research Services said that there had been a rise in inquiries from UK and other European clients concerned about whether their portfolios included firms operating in Sudan. “Over the last few months, we’ve been contacted by five or six larger institutional players,” he said. “A year ago, we had hardly any inquiries.” He said that the inquiries were from companies with an interest in socially responsible investment (SRI) as well as nonSRI investors.

“We would expect ethical retail funds to potentially divest and be aware of these kinds of issues,” he said. “The fact that it’s now getting on to the radar screens of nonSRI specialists suggests it’s a big issue.”

Weir Group, which is repairing existing pumping equipment in Sudan, told The Timesthat the work was valued at less than £500,000 per annum while group turnover was £941 million.

Petrofac, which has operated in Sudan for many years, said: “We believe that continued and coordinated action by the British Government, the international community and NGOs is the most appropriate way to address this issue with the Government of Sudan and bring about a long-term resolution to the crisis.”

A spokeswoman for Barclays Global Investors said it was Barclays’s policy not to engage in business operations in Sudan or to deal with the Sudan Government, but added: “BGI is one of the largest asset managers in the world and as a result we hold shares in companies on indices across the world.”

The Church of England is a shareholder in Sinopec and Petrochina. Campaigners say that it responded to their concerns immediately and agreed to engage with the companies.

In Parliament, up to 69 MPs have signed an early day motion supporting divestment.

Times Recommends

• ‘Lame duck’ fear for FSA as chief quits
• Storm over bailout of EU's most ailing economy
• Northern Rock to drop 100% savings guarantee