Rachel Reeves has been left embarrassed after the Treasury was forced to delete a tweet claiming she did not put up National Insurance in the Budget.

The post on X, from the department’s official account, said: “Last week we protected working people in the Budget.

“That is why we are not increasing the basic, higher or additional rates of income tax, National Insurance or VAT.”

However, the chancellor announced a major increase to the employers’ rate of National Insurance in the Budget.

Paul Johnson, director of the independent, was among those who criticised the government.

He said: “I’m no expert on rules covering what government depts can/cannot say. But at best this is dubious. And that’s being generous. Increasing NI was the central tax raising measure in the Budget. What is the point in pushing this line?”

Shadow chancellor Mel Stride complained to the Treasury about the “misleading” post, and it has now emerged that it has been taken down.

In a letter to Stride, the department’s top civil servant, James Bowler, said: “The post was linked to the taxes of working people and, as such, the reference applied to National Insurance Contributions levied on employees.

“The fact that employer NICs is increasing was widely documented, most obviously in the Budget document and the Chancellor’s Budget speech. Nonetheless, for the avoidance of doubt, the post has been taken down.”

The government gaffe came as Reeves prepares to deliver her first Mansion House speech as chancellor.

She is set to announce plans to create pension “megafunds” to unlock £80 billion of investment in businesses and infrastructure.