Actress Scarlett Johansson has quit as an ambassador for Oxfam amid a row over her support for an Israeli company that operates in the occupied West Bank.
A spokesman for the actress said she had a "fundamental difference of opinion" with the humanitarian group.
She will remain a brand ambassador for SodaStream, which has a factory in the Jewish settlement of Maale Adumim.
The settlements are considered illegal under international law, though Israel disputes this.
About 500,000 Jews currently live in more than 100 settlements built since Israel's 1967 occupation of the West Bank and East Jerusalem.
'Model for peace'
A statement from Ms Johansson's spokesman published on Wednesday announced that the Hollywood star had "respectfully decided to end her ambassador role with Oxfam after eight years", according to the Associated Press.
"She and Oxfam have a fundamental difference of opinion in regards to the boycott, divestment and sanctions movement. She is very proud of her accomplishments and fundraising efforts during her tenure with Oxfam," it added.
On Thursday, Oxfam issued a statement saying it had accepted Ms Johansson's decision to step down and was grateful for her many contributions.
"While Oxfam respects the independence of our ambassadors, Ms Johansson's role promoting the company SodaStream is incompatible with her role as an Oxfam Global Ambassador," it added.
"Oxfam believes that businesses, such as SodaStream, that operate in settlements further the ongoing poverty and denial of rights of the Palestinian communities that we work to support."
The Avengers star signed up to be a global brand ambassador with SodaStream International Ltd earlier this month, and is due to appear in an advertisement for the firm during Sunday's SuperBowl.
Ms Johansson's statement added: "SodaStream is a company that is not only committed to the environment but to building a bridge to peace between Israel and Palestine, supporting neighbours working alongside each other, receiving equal pay, equal benefits and equal rights."
SodaStream - which makes products that allow people to produce carbonated soft drinks at home - operates one of the hundreds of factories constructed in some 20 Israeli-run industrial zones in the West Bank.
The company's chief executive, Daniel Birnbaum, said his factory was "a model for peace".
"We're very proud to be here and contribute to the co-existence and hopefully the peace in this region," he told Reuters news agency.
However, away from the factory, Reuters quoted one unnamed Palestinian employee as saying "there's a lot of racism" at work.
"Most of the managers are Israeli, and West Bank employees feel they can't ask for pay rises or more benefits because they can be fired and easily replaced," he added.