LONDON, Nov 5 - British Prime Minister Tony Blair will tell business leaders on Monday that his government's policy towards joining the single European currency is unchanged, Blair's spokesman said on Monday. Blair is due to give a speech to the Confederation of British Industry in Birmingham at 1400 GMT. "There will be a section on the euro simply saying the policy remains what it is, no matter what interpretation is put on it," Blair's spokesman told reporters. Chancellor of the Exchequer Gordon Brown said earlier that the government's policy towards joining the single currency was the same as it had been since 1997. Brown reiterated his promise that the Treasury's assessment of its five tests for joining the euro would be "comprehensive and rigorous". Blair's spokesman said: "Our position on the single currency is clear. As we have consistently said, the five economic tests stand on their own merits."