UK Prime Minister Andy Burnham raised with President Trump on Friday the economic consequences for Britain and the United States of Argentina’s measures against an oil project near the Malvinas (Falkland Islands), according to Downing Street’s account of their phone call.

“The Prime Minister raised the economic consequences of Argentina’s coercive measures for the UK and US and reiterated the importance of respecting the Islanders’ right to develop their natural resources,” the UK government said. The call also covered Ukraine, energy and the Middle East.

The project is Sea Lion, an oilfield north of the islands run by Israel’s Navitas Petroleum and Britain’s Rockhopper Exploration. Argentina has opened sanctions proceedings against dozens of people and companies tied to it, and asked the international Law of the Sea tribunal in Hamburg to order a halt. The tribunal will hear that request on Nov. 10 and 11.

A bill before Argentina’s Congress would extend the sanctions to affiliates, shareholders, financiers and suppliers of companies working in the islands. It has stalled in the Chamber of Deputies, the lower house. The day before the call, US Deputy Secretary of State Christopher Landau said in Buenos Aires that Washington is watching how the bill could affect American companies. Argentina’s foreign minister, Pablo Quirno, replied that the law is not aimed at any company in particular.

Burnham also spoke on Friday with Chile’s President José Antonio Kast. Downing Street said he raised the UK’s interest in the islanders keeping the right to self-determination, and the two agreed to work together on modernizing their defense capabilities. Kast backed Argentina’s sovereignty claim during a state visit to Buenos Aires in April.

Argentina’s case goes before the Hamburg judges on Nov. 10.