The world's big powers have been told to expect a formal response as soon as today from the Tehran government that sets out an initiative designed to restart negotiations over Iran's nuclear programme.

The letterfollows a conversation yesterday between Javier Solana, the European Union's foreign policy head, and Saeed Jalili, Iran's chief nuclear negotiator, that was described by Mr Solana's office as inconclusive. Further talks "were not ruled out", a spokesman said.

Iranian state television said Mr Jalili "stressed the continuation of talks" and "contacts" in the phone call.

The Massachusetts healthcare programme widely seen as a test case for universal health coverage in the US faces mounting opposition from doctors who say the reform is failing.

More than 250 physicians in the state have signed an open letter warning that the healthcare plan, which was signed into law in April 2006 by Mitt Romney, the former Republican governor of Massachusetts, is "already proving fiscally unsustainable'.

When Bill Barrett Corp, a small US natural gas producer, first went to Utah's Nine Mile Canyon in 2002 to begin drilling, it sought permission to drill fewer than 100 wells. But the price of natural gas has rocketed in the intervening years and now Bill Barrett is seeking approval for 800 more.

Barack Obama and John McCain on Monday stepped up their increasingly tetchy exchange over high petrol prices, with Mr Obama accusing his rival of being in the "pocket of big oil' and Mr McCain accusing his opponent of hypocrisy.

Mr Obama, whose opinion poll numbers have slid sharply since his trip to Europe and the Middle East last month, on Monday unveiled a "comprehensive energy plan' that promised to wean the US off foreign oil while providing short-term relief to consumers.

Japan Tobacco has already had its fair share of bad news this year.

But the world's third-largest cigarette company, with brands such as Camel and Benson and Hedges, is likely to face further turbulence in the months ahead.

The beleaguered JT began the year inauspiciously with a tainted food scare, which battered sales in its food division.

Then came the launch of "Taspo' last month, an age verification card that aims to crack down on under-age smoking but is also expected to be a significant factor behind a forecast 5 per cent fall in JT's cigarette sales.

Petrobras is to reduce exploratory activities abroad in order to concentrate on exploiting a potentially huge Brazilian offshore oilfield, according to the company's president and chief executive.

Jos

Sinopec has made an approach to Imperial Energy, the London-listed oil and gas explorer, which could derail takeover talks between the UK group and India's ONGC.

The Chinese state-owned oil group, also known as China Petroleum & Chemical Corporation, made an approach to Imperial last week and is in the process of conducting due diligence on a formal offer.

Brazil is preparing to take action against the US over what it says are illegal subsidies and other trade barriers following the collapse of the Doha round of talks at the World Trade Organisation in Geneva last week.

Brazil is preparing to take action against the US over what it says are illegal subsidies and other trade barriers following the collapse of the Doha round of talks at the World Trade Organisation in Geneva last week.

Thailand will start to phase out five months of diesel subsidies this weekend, the energy minister said, a move likely to fuel inflation that is running at a 10-year high and raising the chances of more interest rate rises.

Poonpirom Liptapanlop, energy minister, told reporters the government had decided to end a subsidy of 0.4 baht (one US cent) a litre of diesel.
Reuters, Bangkok