George W. Bush has told European leaders that the US will reduce farm subsidies, but only if they agree to make tariff cuts. His words come as negotiators make a last-minute push to reach a deal in WTO talks.

"We're committed to reducing our agricultural subsidies in order to advance the process. We expect others to follow suit in market access," Bush said after discussions with European Commission president Jose Manuel Barroso and German chancellor Angela Merkel in an EU-US summit.

Bush's comments come as the clock ticks on the troubled Doha round, which has been hindered since its launch in 2001 by persistent divisions over agricultural subsidies and tariffs.

They also coincided with a plea from the head of the World Trade Organisation's negotiations on farm trade, Crawford Falconer, who pressed the United States to make a more ambitious offer on those subsidies.

In a letter to world negotiators, Mr Falconer called for a new approach to reducing subsidies and tariffs, suggesting in particular that the United States could improve its subsidy reduction offer by at least another 14 per cent.

The Falconer paper reveals wide gaps between countries' negotiating positions - which bodes poorly for wrapping up a deal any time soon.

The United States wants to see developing countries shelter just a handful of products from tariff cuts so it can increase farm exports to that burgeoning market, while India wants up to 20 per cent of its tariff lines to be covered.