LONDON, June 5 (Reuters) - Here are the main issues between the United States and Iran as they seek a deal to end their war, which is now in its fourth month:

HORMUZ AND GULF BLOCKADE

Iran's closure of the Strait of Hormuz, normally the conduit for around a fifth of global oil and liquefied natural gas shipments, has caused an unprecedented oil supply shock, driving up fuel, food and fertiliser prices.

Reopening the strait is Washington's top priority and Tehran's main point of leverage, but it could take time.