British Prime Minister Gordon Brown's pressed Prime Minister Ehud Olmert to lift constraints on the Palestinian economy. Brown's office said on Tuesday that Brown asked Olmert to act during talks in London. Israel is restricting cash shipments to Gaza banks in order to weaken Hamas, but Brown said the stance was damaging the wider Palestinian economy and harming prospects for peace. On Monday, Brown met with Palestinian Authority Prime Minister Salaam Fayad. Palestinians say that cash shipments to Gaza are used by Fayad to pay government employees loyal to PA President Mahmoud Abbas. Similarly, on Sunday, top international aid officials warned in a letter to Olmert that Israeli restrictions on cash shipments to Gaza banks were largely counterproductive and ultimately harm Palestinian moderates. The letter, obtained by AP, was signed by World Bank President Robert B. Zoellick, International Monetary Fund Managing Director Dominique Strauss-Kahn and international Mideast envoy Tony Blair. It marked the highest-level intervention on the issue yet, following a growing cash crunch in Gaza. The three also expressed concern about a decision by two Israeli banks to sever correspondent relationships with Palestinian counterparts.