Relations between Mrs Beckett and her No 2 reached breaking point yesterday after she refused to allow Mr Hoon the chance to answer questions in yesterday’s monthly Foreign and Commonwealth Office session in the House of Commons, The Times has learnt.

The decision produced the strange spectacle of Mr Hoon sitting beside Mrs Beckett throughout the 55-minute session yesterday without saying a word to the House or to his ministerial colleagues. Instead he buried himself in his notes and appeared oblivious of what was going on around him.

The Times understands that the incident followed a furious face-to-face row on Monday over who should answer questions on Europe — an area that Mr Hoon guards jealously as his own. Last week Mrs Beckett informed her ministerial colleagues that she would take the lead on questions about Europe, restricting Mr Hoon to the subject of northern Uganda. When ministers and officials met on Monday to prepare for yesterday’s questions, Mr Hoon repeatedly demanded to know why she had taken the decision. Mrs Beckett replied: “I am the Foreign Secretary and that’s it.”

The row culminated in Mrs Beckett’s unusual suggestion that Mr Hoon should consider staying away from yesterday’s questions. The Europe Minister expressed astonishment, saying: “Margaret, you can’t stop me from coming to Foreign Office Questions.” She is understood to have replied: “Well, I can’t physically stop you.”

Yesterday Mr Hoon appeared to reject the chance to speak on northern Uganda and left the question to his colleague Kim Howells. One source called Mrs Beckett’s decision “petty”. Foreign Office insiders insisted that she was following the advice of officials. In May Mr Hoon was demoted from the Cabinet when he lost his position as Leader of the Commons and was made Europe Minister with the right to attend Cabinet.

Tony Blair is understood to have wanted to make him the Constitutional Affairs Secretary, taking over from Lord Falconer of Thoroton, but government lawyers advised that such a move would be “constitutionally difficult”.

Another source said that Mr Hoon’s role in advising the Prime Minister on developments over the European constitution “was in his job description” and expressed bemusement that the Foreign Secretary should feel the need to challenge it. The Prime Minister had asked the Europe Minister to report to him directly over the European constitution, which has created some tension in the Foreign Office. “Geoff is trying to deliver on this,” the source said.

“He has been totally reasonable, but Margaret appears determined not to let him speak.”

Friends of Mrs Beckett pointed out that Mr Hoon had been demoted and that there was no reason for a rift with the Foreign Secretary. “Geoff Hoon thought that he was going to be co-secretary but that was never the case. Margaret is doing what the Foreign Secretary should do and deal with Europe.”

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