Twenty20: Surrey's Alec Stewart concerned at plans for city-based tournament

Stewart, 53, played in 133 Test matches for England between 1989 and 2003

Alec Stewart feels plans for a new city-based Twenty20 tournament may not be enough to help counties in debt, and has concerns over how it may affect other formats of the game.

The eight-team event, set to begin in 2020, was outlined by the England and Wales Cricket Board (ECB) last week.

"I'm all for bettering things, but what is it going to look like?" Surrey director of cricket and ex-England skipper Stewart told BBC Sport.

"Even the ECB doesn't know."

The new format is comparable with other high-profile T20 tournaments such as the Indian Premier League (IPL) and Australia's Big Bash League - both of which enjoy huge success and attract most of the world's best limited-overs players, drawing large crowds.

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The tournament would involve eight city-based teams, rather than the 18 counties who traditionally contest the main domestic competitions, but counties would be guaranteed payment of £1.3m a year.

In announcing the plans, the ECB said it would help make cricket a part of "mainstream conversation" and "relevant to a whole new audience".

Stewart explained: "My concern, which I know a lot of other counties have - those who might not be able to speak about it because they are not in the same financial position - is that we are being asked to vote on something very soon, when we don't know exactly what we are voting for.

"To be asked to vote on an unknown is a bit dangerous.

"Is it being done for the good of all cricket, or is Test cricket, four-day cricket, 50-over cricket going to become second, third option or fourth option?

"There are a lot of counties in a terrible financial state. This £1.3m a year that helps them - is that enough to save them? I don't know."

The plans at a glance:

• Eight new teams playing 36 games over a 38-day summer window, with four home games per team

• All games televised, with significant free-to-air exposure

• No scheduling overlap with the existing T20 Blast competition

• An IPL-style play-off system to give more incentive for finishing higher up the league

• A players' draft, with squads of 15 including three overseas players

• Counties guaranteed £1.3m

'The biggest moment in English cricket'

Surrey captain Gareth Batty, who has played 133 domestic T20 matches, said the proposed changes were both "exciting and scary".

"I think of it as going back to the Kerry Packer era. This is the biggest moment certainly in English cricket, if not cricket in the world, since that period," he said.

"I believe that, from a cricket fan point of view, we have to get it right, because if we don't we could be looking at a decade of cricket being put on the back foot.

"So change is good but it's got to be change to make things better than what we've already got and to move the game forward."

Stewart, who appeared in 133 Tests and 170 one-day internationals for England, added: "From a Surrey point of view we don't need it.

"We sell out our T20 home games, so from a purely blinkered Surrey view we would be happy to continue as we are.

"But could the ECB have invested some of this money directly, before going the full hog with a new format, to try and help the financial problems some counties have found themselves in, for example?

"You have to move with the times, and I want this to work, but what damage might there be to the counties' history, too?"