English cricket is on the brink of a "ground-breaking opportunity" to ensure a new city-based Twenty20 tournament becomes reality.

England and Wales Cricket Board chairman Colin Graves will seek to set the wheels in motion at a Lord's meeting on Tuesday morning for the constitutional change which will pave the way for the eight-team competition to begin, appropriately, in 2020.

ECB chief executive Tom Harrison and T20 project lead Mike Fordham presented updated plans for the as yet unnamed venture to representatives of 41 stakeholders - made up of the 18 first-class counties, the MCC, the Minor Counties Cricket Association and the recreational boards - at the Royal Institute of British Architects in Marylebone on Monday.

Harrison broke off briefly to recount details of the proposed format at a press conference, confirming a framework of 36 matches over 38 days in July and August for squads of 15, achieved via a draft system and each with three overseas players.

An element of free-to-air broadcast will be preferred, with a current projection of up to eight matches available to that media stream.

A further key staging post in the ECB's plans came with confirmation that a full house of all 18 counties and the MCC have signed "media rights deeds" - documents authorising the governing body to include the new tournament in its portfolio to be offered to broadcasters in this summer's forthcoming negotiations.

Armed with that mandate, Graves is in position to invite his executive board to order a postal vote - to be completed over the following 28 days, by the 41 stakeholders - for agreement or otherwise that an eight-team tournament, rather than one involving all counties as is currently written into the constitution, can be sanctioned in this case. Assent will be needed from a minimum 31 of them.

In a press release, Graves said: "Tomorrow I will ask the ECB board to trigger a change in our Articles of Association to enable the introduction of the proposed new T20 competition.

"We face a ground-breaking opportunity in the weeks and months ahead - and if our members embrace it, the ECB will work with everyone in the game to ensure this huge potential and the investment that will come with this delivers an even stronger future for the game."

Some counties had previously wavered, despite last September's 16-3 show-of-hands vote broadly in favour.

The format will be similar to the Big Bash in Australia or the IPL (Getty)

The ECB has since announced each club will receive an annual £1.3million share of projected tournament revenue - and asked after the first of Monday's meetings if he is aware of any significant residual doubts among the counties, Harrison said: "No, I'm not.

"We've been very open and transparent about debating this. We've had the hard conversations ... and we've got to a point where everyone is comfortable about their own role in this."