This is the text of the letter which the First Minister has now sent to Robert Menendez, the US senator who is demanding that Scottish Ministers attend a senate hearing in the US to discuss the release of Abdelbaset Ali Al-megrahi from prison in Scotland on compassionate grounds.

Dear Senator Menendez

Thank you for your letter of 29 July.

I have made clear in my letters to you and to Senator Kerry that the Scottish Government’s decision to decline your previous invitation for the Cabinet Secretary for Justice and Dr Fraser to attend a hearing in the US was based on principle rather than on any issue of practicality.

The most appropriate way for us to assist the Foreign Relations Committee is to provide a statement of the position of the Scottish Government, as I have done, and to answer any questions that the Committee may have in writing, as we have also done.

Scottish Ministers and public officials are properly accountable to the Scottish Parliament and not to other legislatures. It is difficult to envisage circumstances in which serving members of the US Government would agree to appear as witnesses in hearings or inquiries held by the legislature of another country, and there are many high-profile and indeed current examples of the US Government declining such invitations.

Your letter again seeks to link BP with the decision made by the Scottish Government to grant Mr Al-Megrahi compassionate release. No-one has produced any evidence of such a link because there is none. We have said repeatedly that there has never, at any point, been any contact between BP and the Scottish Government in relation to Al-Megrahi. The statements we have made on this issue are entirely clear and consistent.

It was with concern that I watched you attempt to insinuate such a link on BBC Newsnight on 30th July by citing a letter from Conservative Party peer Lord Trefgarne, the chair of the Libyan British Business Council, to Justice Secretary MacAskill last year. This was one of approximately one thousand representations received by the Scottish Government last year, including many from the USA. You have this letter because the Scottish Government published this last year as part of our comprehensive issue of documentation related to the decision. That being the case, you must also have seen the reply from Mr MacAskill, also published, which stated that his decisions would be “based on judicial grounds alone and economic and political considerations have no part in the process”. In order to avoid any suggestion of misrepresentation, I trust that you will include that fact in future references.

BP’s admitted lobbying on this issue referred to the Prisoner Transfer Agreement (PTA) and with the UK Government. As you must by now be aware, the Scottish Government opposed this agreement from its inception, a position that we have maintained publicly and privately since. Indeed, I revealed the existence of the proposed PTA to the Scottish Parliament in a statement on 7 June 2007. It is perhaps to be regretted that our warnings about the circumstances in which this agreement came into being found no response at that time from the UK Government, the then opposition in the UK Parliament, or indeed from the United States Senate.

Finally, you and some of your Senatorial colleagues, have suggested that the Scottish Government have sought to pass responsibility to others for the release of Al-Megrahi. That is simply not the case. Secretary MacAskill took the decision following the precepts and due process of Scots law and jurisdiction – the same jurisdiction which over a period of some 20 years led Scotland to play the leading role in investigating, trying, convicting and incarcerating Al-Megrahi. We do not resile from our responsibility in making that decision.

The point we make is a different but a quite simple one. Please do not ascribe to the Scottish Government economic or commercial motives for this decision when there is no evidence whatsoever for such a claim.

If you wish to investigate commercial or indeed other motivations surrounding this case, then call the former UK Ministers and Prime Ministers who were involved in proposing, negotiating and then signing the PTA and, of course, where there is a public record of admission that business and trade, along with other issues, were factors. In this light your decision not to proceed with the draft invitation to offer evidence to former Prime Minister Blair, who actually signed the proposed PTA in May 2007, seems puzzling.

These people, of course, may have had, and indeed in some cases have conceded, motivations other than justice considerations. However, they did not take the decision on Mr Megrahi.

I am copying this letter to Senator Kerry.