This week, I am sponsoring legislation in the United States Congress that will end US military involvement in Libya for the following reasons:

First, the war is illegal under the United States constitution and our War Powers Act, because only the US Congress has the authority to declare war and the president has been unable to show that the US faced an imminent threat from Libya. The president even ignored his top legal advisers at the Pentagon and the department of justice who insisted he needed congressional approval before bombing Libya.

Second, the war has reached a stalemate and is unwinnable without the deployment of Nato ground troops, effectively an invasion of Libya. The whole operation was terribly ill-considered from the beginning. While Nato supports the Benghazi-based opposition (situated in the oil-rich north-east), there is little evidence that the opposition has support of the majority of Libyans. The leading opposition group, the National Front for the Salvation of Libya (which had reportedly been backed by the CIA in the 1980s), should never have launched an armed civil war against the government if they had no chance absent a massive Nato air campaign and the introduction of Nato troops. Their reckless actions, encouraged by western political, military and intelligence interests, created the humanitarian crisis that was then used to justify the Nato war campaign.

Third, the United States cannot afford it. The US cost of the mission is projected to soon reach more than $1bn, and we are already engaged in massive cutbacks of civil services for our own people.

It is not surprising that a majority of Republicans, Democrats and independents alike think the US should not be involved in Libya.

This war is misguided. An invasion would be a disaster. Nato already is out of control, using a UN mandate allowing for protection of civilians as the flimsy pretext for an unauthorised mission of regime change through massive violence. In a just world, the Nato commander would be held responsible for any violations of international law. As a means of continuing the civil war, Nato member France and coalition ally Qatar have both admitted shipping weapons to Libya, in open violation of the United Nations arms embargo.

In the end, the biggest casualty of this game of nations will be the legitimacy of the UN, its resolutions and mandates, and international rule of law. This condition must be reversed. The ban on arms supplies to Libya must be enforced, not subverted by Nato countries. The US must cease its illegal and counterproductive support for a military resolution now.

The US Congress must act to cut off funds for the war because there is no military solution in Libya. Serious negotiations for a political solution must begin to end the violence and create an environment for peace negotiations to fulfil the legitimate, democratic aspirations of the people. A political solution will become viable when the opposition understands that regime change is the privilege of the Libyan people, not of Nato.