If Mr Kinnock does not get satisfaction, he is expected to add Britain to the list of six member states he has already threatened to take to the European court if they continue to negotiate bilaterally with the US. Brussels is demanding central control of negotiations so that individual member states are not picked off one by one.
Mr Kinnock's transport directorate also sees the issue as an important test of its authority. Belgium, Denmark, Luxembourg, Sweden, Austria and Finland have so far refused to end their individual talks over so-called open skies agreements on passenger airlines that the US is seeking. Britain's long-standing negotiations over air cargo have not until recently been bracketed with the row over passenger services.
The US has offered each country a number of concessions in its own aviation market in return for greater access for American airlines in Europe. The commission fears this is a back-door route for American airlines to take advantage of moves to open up the internal European aviation market.
The row is set to escalate today when Mr Kinnock asks his commission colleagues to approve proposals for a wide-ranging mandate to negotiate with the US. He is believed to be confident of winning approval.