Selectors will pick a wider squad in about two weeks for the WTC decider at The Oval from June 7th-11th and for the first two tests of the Ashes series, which starts on June 16th in Birmingham.
Apart from a defiant 200 against South Africa in December, lefthander Warner has struggled for runs in recent tests, making a total of 26 in three innings in the recent tour of India before returning home injured.
Despite that, head coach and selector Andrew McDonald said last month Warner was in Australia's plans for the WTC final.
Warner was included in Cricket Australia's list of 24 nationally contracted players on Thursday but Bailey stopped short of saying it was an endorsement for the Ashes.
"I think Dave, like any player is, is at the mercy of selection," Bailey told reporters.
"The Ashes is a huge series and we'll be looking to pick our best team. We're going to have to have our best team playing incredibly well to challenge England over there, the way they're playing at the moment."
Asked why Warner would not be picked in an Ashes squad if he were to play in English conditions during the WTC final, Bailey said he endorsed McDonald's point that England were a different team to India.
"I support Andrew's comments on that around David.
"I think there's a number of differences (between the teams). But we're a couple of weeks away from announcing that squad."
Warner averaged 9.50 in the 2019 Ashes in England, the worst ever by an opener to play 10 innings in a series.
Travis Head replaced him at the top of the order in India and batted superbly in the last two tests but selectors said his promotion was a short-term fix.
Opener Marcus Harris was a surprise inclusion in the list of contracted players, having played the last of his 14 tests against England in January 2022.
Matt Renshaw, another opener, and middle order batsman Peter Handscomb were overlooked despite both playing in India.
Bailey said Renshaw and Handscomb played in India because of their skill-sets but Harris was contracted with English conditions in mind, along with the home tests and a tour of New Zealand next year.
Harris has averaged 19.75 in seven tests against England, compared to a career average of 25.29.
"We certainly rate Harry's (Harris) ability in those conditions - really good strong record in England as well," said Bailey.
