The Clinton Foundation reportedly is seeing an increase in contributions from foreign governments after ending a self-imposed ban on such donations, raising new ethical questions as Hillary Clinton prepares for a possible 2016 presidential campaign.

According to The Wall Street Journal, which cited the foundation's online database, recent donors to the foundation include the United Arab Emirates (UAE), Saudi Arabia, Oman, Australia, Germany, and a Canadian government agency promoting construction of the Keystone XL pipeline. 

The foundation instituted a foreign gifts ban in 2009 after Hilllary Clinton was named Secretary of State by President Barack Obama. The Journal reports that the ban was not a total one, and some donations were permitted after receiving the approval of State Department ethics officials. Hillary Clinton re-joined the foundation after leaving the State Department in 2013 and has fronted a $250 million endowment campaign.

Ethics experts have told the Journal that the Foundation should re-imposed its ban while Hillary Clinton considers a possible White House bid.

"Now that she is gearing up to run for president, the same potential exists for foreign governments to curry favor with her as a potential president of the United States," said Kirk Hanson, director of the Markkula Center for Applied Ethics at Santa Clara University in California.

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"She can't recuse herself [if she becomes president]," said James Thurber, director of American University‚Äôs Center for Congressional and Presidential Studies. "Whether it influences her decision making is questionable, but it is a legitimate thing to focus on by her political opposition." 

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A foundation spokesman defended the organization's practices on Wednesday. 

"The Clinton Foundation is a philanthropy, period," spokesman Craig Minassian said. "As with other global charities, the Clinton Foundation receives the support of individuals, organizations and governments from all over the world because our programs are improving the lives of millions of people by strengthening health systems, improving access to lifesaving medicines, helping communities confront the effects of climate change, creating economic opportunity and reducing childhood obesity and other preventable diseases." 

He stressed that the foundation discloses all donors. 

The donation tied to the Keystone XL pipeline of a reported $480,000 came from Canada's Foreign Affairs, Trade, and Development, whose website described promoting the Keystone XL pipeline "as a stable and secure source of energy and energy technology" as one of its goals for the 2014-15 fiscal year on its website. The Foundation told the Journal that the donation came from a separate agency office from the one advocating for the pipeline's construction.

Construction of the Keystone XL pipeline has been a hot political topic under the new GOP-led Congress, and Hillary Clinton has repeatedly declined to comment on the issue.

Another donation that could raise eyebrows comes from the Qatari government committee preparing to host the 2022 soccer World Cup, which gave between $250,000 and $500,000 last year. Human rights groups have claimed that over 1,000 migrant workers have died in the process of constructing the infrastructure to host the tournament. 

In all, a tally by the Journal has found that the number of foreign donors doubled in 2014 from the previous year. The UAE donated between $1 million and $5 million last year, while the German government gave between $100,000 and $250,000. Repeat donors include Saudi Arabia, which has contributed at least $10 million since the foundation's founding in 1999, and Australia, which has given at least $5 million. 

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