Ariel SharonAriel Sharon’s last visit to the US, a year ago, was an enormous success for Israel. The prime minister returned home with unprecedented American concessions designed to reward him for his planned evacuation of the 7,000 Jewish settlers from the Gaza Strip.

President George W. Bush told Mr Sharon that he could expect to keep the large settlement blocs Israeli governments have illegally built on the occupied West Bank. He also supported Mr Sharon’s position that Palestinian refugees could not return to land that is now part of the state of Israel.

The outcome of the talks outraged the Arab world and shocked the US’s European allies, desperate to see Washington play a more even-handed role in the Arab-Israeli conflict. Faced with such reactions, the Bush administration has, since then, sought to play down the concessions, insisting that the president was not trying to prejudice the outcome of final peace negotiations between Israelis and Palestinians.

Mr Bush should keep the reactions to this last visit in mind when he hosts Mr Sharon again today at the Crawford ranch. If Washington is serious about advancing peace, Mr Sharon should be told to return to the negotiating table after the Gaza pull-out and to immediately halt the expansion of Jewish settlements on the West Bank.

The mood in the Middle East has changed since Mr Sharon’s last trip. The Gaza withdrawal scheduled for the summer and the January election of Mahmoud Abbas as new Palestinian president have raised hopes for a revival of the political process after more than four years of violence. Mr Abbas had declared an end to the Palestinian uprising and persuaded radical Palestinian factions, including Hamas, to commit to a ceasefire.

Mr Sharon will tell Mr Bush that he is confronted with massive pressure from the settlers’ lobby, forcing him to make concessions on settlement activities. But unless Israel can be made to abide by all its obligations under the US-sponsored road map, the blueprint for a resumption of the peace process, the hopes for progress created over recent months will soon dissipate.

The road map, published in 2003, clearly states that Israel must immediately dismantle so-called “outposts”, illegal new constructions on occupied land. Yet according to Peace Now, the Israeli group, about 50 new outposts have sprung up in the West Bank since that date.

The road map also demands that Israel freeze all settlement activity, including what Israelis refer to as “natural growth”, the expansion within existing settlements. But American policy on settlements has been ambiguous, if not outright unhelpful.

Last week, the administration rightly criticised Israeli plans to add 3,500 new homes to a settlement near Jerusalem. But it has acquiesced to the continued construction of houses within settlement boundaries. It is time for the US to adopt a consistent and tough line on settlements.