Boris Johnson has urged people to "wait and see" over reports he wants to be the Tory candidate for London mayor.
Mr Johnson is one of the best known figures in UK politics
The Henley MP, who has until Monday to decide whether to join the list of Tory hopefuls, said "it won't be long now" before he made an announcement.
The Daily Telegraph earlier said he had spoken to Tory leader David Cameron about the possibility.
Mr Johnson said: "I don't want to cast any aspersions on my own great paper but it wouldn't be the first flyer."
He has the weekend to agonise over his next move before the deadline closes for Tory mayoral hopefuls.
Speaking last week, Mr Johnson said he was "definitely not a candidate" for next year's election, citing the "logistical difficulties" of his position as an MP.
But he added that he was "honoured to be thought of in this context" and that it would be a "fantastic job".
Mr Johnson is one of the best-known Tory MPs, because of his frequent television appearances.
A Conservative Party spokeswoman described reports of his joining the mayoral race as "speculative".
An announcement that Mr Johnson intended to run was posted on his weblog on Friday morning, but was removed a few minutes later as it was not "official".
Mr Cameron previously tried to persuade former BBC director general Greg Dyke to run as an independent candidate with Tory and Lib Dem backing, but this was ruled out.
He also explored the possibility of former CBI chief Digby Jones, now a Labour trade minister, becoming a Conservative mayoral candidate, it emerged last week.
The Conservatives have reportedly been turned down by several other potential high-profile candidates including London Olympics supremo Lord Coe, radio presenter Nick Ferrari and former Metropolitan Police chief Lord Stevens.
In April the party set out a five-month timetable to find a candidate - shortlisting applicants to go on to an "open primary" - with all Londoners on the electoral roll being allowed to vote.
The deadline for applications is next Monday, with a shortlist drawn up by 3 August.
After a series of hustings, the primary will be held, closing on 26 September.
The winner will be announced at the Tory conference in September.
Mr Johnson is the shadow higher education minister and was previously editor of the Spectator magazine.
Mr Livingstone has been London mayor since 2000.