The former prime minister will provide the statement to the Committee on Privileges as he fights to salvage his political career.
Johnson will appear before the panel on Wednesday for televised cross-examination, and is expected to present his written evidence before then.
In an interim report, the Committee on Privileges said the evidence strongly suggests that the coronavirus rule breaches in No. 10 should have been “obvious” to Johnson.
They are examining evidence on at least four occasions that he may have deliberately misled MPs with his assurances to the House of Commons that the rules were followed.
Johnson’s allies said he would provide a “detailed and compelling” account to the committee before his appearance, showing that he “did not knowingly mislead the House.”
The Sunday Times reported that it will point to a series of previously undisclosed WhatsApp messages from senior officials and members of his 10 team that show he had trusted their advice when he made his remarks to Parliament.
It will also publish messages showing that other senior figures in Downing Street believed the meetings were covered by the “workplace exemption” in the lockdown rules.
The committee inquiry is chaired by Labor Harriet Harman, although the seven-member panel has a Conservative majority.
The committee will publish its findings on whether Johnson was in contempt of Parliament and make a recommendation on any punishment, but the final decision would rest with the full House of Commons.
Prime Minister Rishi Sunak has said he will not try to influence parliamentarians on the committee and indicated he would give Conservative MPs a free vote on any recommended sanctions.
Asked if he was not concerned that a suspension of more than 10 days could trigger a by-election in Johnson’s Uxbridge and South Ruislip seat, Sunak added: “This is a Parliament, a House matter. It’s not right for the government to get involved.”