Scarlett Johansson has been a global ambassador for Oxfam since 2007. In that time she has travelled around the world, meeting people that the charity works with - including refugees, children unable to afford schooling, and survivors of natural disasters - and raising awareness of programs that urgently need funding.

Scarlett Johansson has been a global brand ambassador for SodaStream - an Israeli company that makes a range of products for carbonating soft drinks at home - for about a month, and is due to appear in the company's Super Bowl ad on 2 February. The company's main production site is located within an illegal Israeli settlement in the West Bank, Ma’ale Adumim. It's one of the settlements that Oxfam opposes "all trade" with, saying they "further the ongoing poverty and denial of rights of the Palestinian communities that we work to support".

All week there have been calls from a multitude of groups for Johansson to drop her deal with SodaStream in recognition of its violation of international law. The US Campaign to End the Israeli Occupation started a petition calling for her to choose not to be "the face of the occupation", arguing that "as an Israeli settlement manufacturer, [SodaStream] exploits Palestinian land, resources and labor and actively supports Israel's military occupation".

This contradiction between her longstanding charity work and her most recent ad deal couldn't stand - so she's chosen SodaStream over Oxfam:

Oxfam has accepted Scarlett Johansson’s decision to step down after eight years as a Global Ambassador and we are 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. 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. Oxfam is opposed to all trade from Israeli settlements, which are illegal under international law. Ms. Johansson has worked with Oxfam since 2005 and in 2007 became a Global Ambassador, helping to highlight the impact of natural disasters and raise funds to save lives and fight poverty.

Who can blame her? It's not like that Super Bowl ad is incredibly tacky or anything. And imagine the free soda she must get. Quite the deal for the actor.

In its defence, the current CEO of SodaStream, Daniel Birnbaum, told Forward magazine that he inherited the "pain in the ass" factory that was built by the company's previous owners and that he would "never" have chosen to build it there himself. However, as 500 of the plant's 1,300 employees are Palestinian and closing it down now would financially ruin them, he "will not throw our employees under the bus to promote anyone’s political agenda."

Johansson released a statement last week when the controversy first appeared, defending her choice: "I remain a supporter of economic cooperation and social interaction between a democratic Israel and Palestine. SodaStream is a company that is not only committed to the environment but to building a bridge to peace between Israel and Palestine, supporting neighbors working alongside each other, receiving equal pay, equal benefits and equal rights."

Alas, it seems the dialectical merger of the two ambassadorial roles was futile.