Bar operator Regent Inns has been given a "put up or shut up" ultimatum in its quest to snap up Tiger Tiger owner Urbium.
Regent, the owner of Walkabout bars and the Jongleurs comedy chain, was given a month by the Takeover Panel to either say it plans to make an offer or walk away.
The deadline comes two weeks after Urbium, which owns the Digress bar in Newhall Street, Birmingham, said it had rejected an approach from Regent because it was too low and mainly shares-based.
Urbium also said at the time that there was little strategic fit between the two "very different" businesses.
If Regent decides not to make an offer by midday on July 21, it will be prevented from making another move for six months.
London-based Urbium has 29 UK outlets, including eight Tiger Tiger bars at locations including Glasgow, Manchester, Leeds and Newcastle, as well as one-off bars such as London's Sugar Reef and Zoo Bar.
Regent has 48 Australian themed Walkabout bars, one on Broad Street, Birmingham, which specialise in broadcasting international football and rugby matches, as well as 17 Jongleurs comedy clubs n Property tycoon Robert Tchenguiz is thought to be on the brink of buying two large pub companies as his thirst for deals showed no sign of easing.
Mr Tchenguiz is understood to be finalising deals for SFI - the owner of the Slug and Lettuce and Bar Med chain - and the Heritage Pub Company for around £160 million.
It is expected that SFI will be acquired for £80 million through Laurel to expand its portfolio of bars on the high street.
The Heritage Pub Company, which is based in Derby, has 231 sites around the UK.