Gordon Brown will today be accused by the President of the European Parliament of pandering to Eurosceptics for "short-term tactical and personal reasons".
In an unprecedented attack, Pat Cox MEP will use a speech to the CBI conference in Birmingham to suggest that the Chancellor has indulged in anti-European "propaganda" to win round the British press.
However, the Treasury said that the Chancellor would "make no apologies" for standing up for the British national interest.
Mr Brown will underline his own stance on the issue this week by urging Europe to match the United States on economic reform as he unveils a new Anglo-American pact to boost trade.
In his own speech to the CBI tomorrow, he will declare that: "Europe's economic future depends on an ever-deeper and closer economic relationship" with the US. Mr Brown caused controversy last week when heused newspaper interviews to attack parts of the proposed EU constitution that would curtail Britain's right to set its own economic policy.
But Mr Cox will warn that such views risk the "marginalisation" of the UK. But in a speech that Brown aides regard as a direct attack on the Chancellor, the European Parliament President will say: "Anyone who regards themself as pro-European should refrain from encouraging fantasies and misconceptions about Europe for short-term tactical or personal reasons."
Mr Cox will state that Britain's vocal Eurosceptic press meant that there was "always a temptation for politicians, who understand that Europe is vital to Britain's interests, to make common cause with the Eurosceptics and that "pandering to anti-European sentiment ... risks the marginalisation of Britain.
"Britain's case falls on deaf ears with its European colleagues when it is couched in Eurosceptic language."
Mr Cox will claim that it is "simply nonsense" to suggest that there is an inexorable slide to tax harmonisation when Britain and many other nations have said they would veto such moves. "I would urge British political leaders to rise above the daily diet of scary kites flown about EU superstates, tax harmonisation and floods of immigrants," he will say.
His claim that the Chancellor is motivated by "personal reasons" - furthering his ambition to become Prime Minister - infuriated the Treasury last night. A spokesman said: "People would expect the Government to stand up for Britain's national interest ... But pro-Europeans can best promote their ideals when Europe is seen to be making progress towards economic reform and stronger growth and that is the case we have been making."
More importantly, Treasury sources pointed to proposals from Fritz Bolkestein, European Commissioner for the single market, to harmonise taxes for companies. "The fact that the commission is planning to land on us plans to harmonise company tax proves that," a source told The Independent.Reuse content