Oil prices were largely steady Wednesday as marathon talks aimed at preventing Iran from getting a nuclear bomb went into a nail-biting extension.
Traders meanwhile awaited the latest snapshot of US crude inventories for indications of demand in the world's biggest economy.
Brent North Sea crude for delivery in May edged up seven cents to stand at $55.18 a barrel around midday in London.
US benchmark West Texas Intermediate (WTI) for May slipped 34 cents to $47.26 a barrel compared with Tuesday's close.
"The nuclear talks with Iran extended over the deadline. However, it seems to lean towards an agreement," said Daniel Ang, investment analyst with Phillip Futures.
"Iran produces a high volume of crude and if the sanctions are eventually lifted, this will push both the WTI and Brent downwards for a prolonged period," he said.
Industry is the cornerstone of Iran's economy, but it has been hit hard by the American and European embargo imposed since 2012.
Crude dealers are also awaiting the latest official US stockpiles report to be released later Wednesday.
Oil reserves likely rose by 4.2 million barrels in the week ending March 27, according to a survey by Bloomberg News.