During their time in office, German official development assistance came to 10.83 billion euros by 2013, making the country the world's third largest donor in 2012 and 2013.

Also he created Engagement Global gGmbH, a state owned company, which is now responsible for founding of development aid initiatives of civil society in Germany.

In early 2012, Niebel met with Myanmar's opposition leader Aung San Suu Kyi and was soon among those pushing for a complete removal of sanctions against the country rather than a more gradual easing.

[5] Under Niebel's leadership, Germany joined the United States and several other European states in late 2012 in partially suspending official development assistance to Rwanda after U.N. experts said senior Rwandan military officials had equipped, trained and directly commanded M23 rebels who briefly seized the city of Goma in eastern Democratic Republic of Congo.

[6] Only after negotiations with Rwandan Foreign Minister Louise Mushikiwabo in early 2013, Niebel agreed to use the unfrozen aid for economic development and vocational training rather than direct budget support.

[14] In January 2011, Niebel met with Israeli Deputy Foreign Minister Danny Ayalon and signed a joint Declaration of Intent aimed to increase bilateral cooperation in effort to assist developing nations, agreeing to work towards the rehabilitation of the contaminated Lake Victoria in Kenya, the main source of water for several states and one of the sources of the Nile River.

[17] In March 2011, Niebel caused diplomatic tensions when he accused the United Nations-backed military alliance operating in Libya of hypocrisy.

"[18] He also criticized the French government of President Nicolas Sarkozy for a lack of consultation and Catherine Ashton, the EU's foreign policy chief, for “suboptimal” co-ordination.

The centre-left opposition accused the minister of "brazen abuse" of office, which risked undermining Germany's efforts to promote good governance in countries like Afghanistan.

[20][21][22] On 2 May 2012 the German TV magazine Monitor reported that after Niebel took the office of Federal Minister of Economic Cooperation and Development over 40 members or staff of the FDP were hired to work in his ministry.

[23] Later that year, he appointed a Green Party member as head of the newly established German Institute for Development Evaluation (DEval).