* UK working to ensure energy sanctions are enforced - Hague
* Who is a target "depends on how they behave" - Hague
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LONDON, April 26 (Reuters) - Britain hopes for international agreement in the coming week on setting up a fund to help Libya's rebel-held east, Foreign Secretary William Hague said on Tuesday.
The fund is aimed at helping the rebel's interim national council help pay public sector salaries and with other costs.
"In the coming week, we hope to agree internationally the process for establishing a temporary financial mechanism to provide a transparent structure for international financial support for the financial requirements of the (national council) such as public sector pay," Hague told parliament.
Kuwait will contribute 50 million Kuwaiti dinars ($182 million) to the rebel council, a rebel leader said on Sunday.
Hague said coalition aircraft had carried out more than 3,500 sorties and 1,500 strike sorties since NATO took control of military operations in Libya at the end of March.
"This action has seriously degraded (Libyan leader Muammar) Gaddafi's military assets and prevented widespread massacres planned by Gaddafi's forces," he said.
Asked if he was looking at tightening restrictions on supplies of petrol and diesel to Gaddafi's forces, Hague said it was important existing sanctions were enforced.
"We are doing a lot of work on making sure they are rigorously enforced by other countries ... So we are looking at that at the moment," he said.
Gaddafi's government has circumvented U.N. sanctions banning dealings with Libya's National Oil Company by having petrol delivered to Tunisia, then transferred to Libyan vessels.
Hague refused to talk about specific targets when asked about calls for NATO air strikes to target Gaddafi and associates.
"Who or what is a target depends on how they behave," he said, without elaborating.
NATO forces flattened a building inside Gaddafi's Bab al-Aziziyah compound on Monday, in what his officials said was an attempt on the Libyan leader's life.
Russian Prime Minister Vladimir Putin said on Tuesday the coalition had no mandate to kill Gaddafi.
Hague announced that John Jenkins, the current British ambassador to Iraq, would soon take over from Christopher Prentice as head of a British diplomatic team sent to talk to rebels in the eastern Libyan city of Benghazi.
Hague rejected a call from lawmaker John Baron, from Prime Minister David Cameron's Conservative Party, for a new debate and vote in the British parliament on the Libya operation.
Baron and several other Conservative members of parliament argue that the goal of the Libya operation has shifted from humanitarian to "regime change" since parliament overwhelmingly approved Britain's role in a no-fly zone last month. (Reporting by Mohammed Abbas, Adrian Croft; Editing by Alison Williams)