Architect Zaha Hadid is understood to have considered legal action against the Department for Culture, Media and Sport after it made false allegations that the aquatics centre for the 2012 Olympic games had gone significantly over budget.

Hadid's practice forced the department to apologise in writing after culture secretary Tessa Jowell publicly announced that Hadid had been sent "back to the drawing board" at the Thames Gateway Forum in November last year.

Jowell said the cost of the project had almost doubled because of a change in specification. This was untrue.

A spokesperson for Hadid's firm said: "Tessa Jowell's statement did significantly upset this office and a meeting did take place after to discuss what action should be taken."

Hadid's practice, along with fellow scheme designer S&P Architects, demanded an apology from the government. The letter, from Nicola Roche, the director of sport at the department, dated 21 December 2005, agreed that Hadid did not change the specification.

I can confirm Zaha Hadid did not change the specification

Extract from DCMS letter

It said: "I can confirm that Zaha Hadid Architects did not change the specification, nor have they been responsible for any proposed rise in costs. The secretary of state's comments about the aquatics centre should be seen in the context of a continuing process of controlling the potential for costs to rise as is the case with any project."

At the time, Hadid was backed by a number of high-profile architects, including the mayor's chief architect Richard Rogers, who made his feelings clear in a letter to The Guardian. In it, he stressed Hadid's project had not gone over budget.

He said: "I wish to make clear that the winning design by Zaha Hadid Architects has not exceeded the construction cost of £75m. All competition schemes were scrutinised by a technical panel against clear cost and deliverability criteria. The Hadid design was in full compliance with the brief requirements."