Several types of Non-Governmental Organizations (NGOs) could potentially sue the U.S. administration if they believe there's a case to be made for violation of laws like Section 620I of the Foreign Assistance Act:

Human Rights NGOs:

• Amnesty International USA: Known for advocating against human rights abuses globally, they might have the inclination and resources to engage in legal action if they believe U.S. policy violates international human rights norms or domestic laws.

• Human Rights Watch: They focus on documenting and advocating against human rights abuses, and could potentially be involved in legal cases concerning policy violations.

• The Center for Constitutional Rights (CCR): This organization has a history of engaging in litigation against the U.S. government on issues of constitutional rights, international law, and human rights abuses.

Humanitarian Aid NGOs:

• Doctors Without Borders/Médecins Sans Frontières (MSF): If U.S. policies directly impact their ability to provide aid, MSF could consider legal action, though they generally focus on operational responses.

• International Rescue Committee (IRC): An organization that might sue if its operational capacity is being hindered by U.S. policy, particularly in conflict zones.

Peace and Security NGOs:

• Win Without War: This coalition of organizations might engage in legal action to challenge U.S. military aid policies they see as contributing to human rights violations or conflicts.

• Global Justice Now: Focuses on challenging global injustices, including issues related to armaments and conflict.

Environmental NGOs:

• While not directly related to Section 620I, if arms sales or aid policies lead to environmental degradation or impact climate refugees, organizations like:
  • Greenpeace USA
  • The Sierra Club might have an interest, particularly if there's an environmental angle to the humanitarian crisis.

NGOs with Legal Capabilities:

• ACLU (American Civil Liberties Union): Although primarily focused on civil liberties within the U.S., they sometimes engage with international law issues.

• EarthRights International: Combines environmental justice with human rights, which could intersect with arms sales and humanitarian aid.

Steps for NGOs to Take Legal Action:

1. Establish Standing: The NGO must show it has been directly affected by the policy or action in question, which can be challenging but is possible if they operate in affected regions.

2. Legal Strategy: They would need to:

   • Draft a complaint detailing the legal violation.
   • Identify the appropriate court (likely federal due to the parties involved).
   • Seek legal representation with experience in federal litigation, constitutional law, and international law.

3. Funding and Resources: Litigation against the government can be expensive and lengthy. NGOs would need to secure funding or pro bono legal support.

4. Alliances: Often, multiple NGOs band together to share resources, expertise, and increase the impact of their legal challenge.

5. International or Domestic Focus: Decide if this is better pursued in U.S. domestic courts or if there's a relevant international legal venue (like arguing before international bodies if applicable).

6. Public Advocacy: While suing, these organizations might also engage in public advocacy to raise awareness and put political pressure on the administration.

Remember, any legal action would need to overcome hurdles like standing, the political question doctrine, and executive privilege. NGOs typically engage in such litigation when they have strong evidence of legal violation and believe the courts can provide a remedy or that the lawsuit can prompt policy change through public or political pressure.