The UK is still in the midst of unseasonably warm weather but cool heads will be required as the battle between 21st Century Fox and Comcast for ownership of Sky is set to heat up this week.

Comcast is expected to lodge a formal $31B bid for Sky this week and the British government is thought to be on the brink of finally giving Rupert Murdoch’s Hollywood the final greenlight to buy the 61% of the European pay-TV firm that it currently does not own.

These factors will likely then prompt 21st Century Fox into raising its bid for the company, potentially leading to a major bidding war for the Bulletproof broadcaster.

Comcast has until Friday July 13 to publish the full terms of the $31B offer that it made on February 27. This bid, which amounted to £12.50 per share, was a 16% premium on Fox’s December 2016 £10.75 per share offer.

British Culture Secretary Matt Hancock is also expected to formally approve 21st Century’s ability to takeover Sky this week. This process has taken well over 18 months and has received scrutiny from regulator Ofcom and the Competition and Markets Authority. On June 19, Hancock published a series of resolution that Fox, and potentially Disney, if it acquires the rival studio, would need to put in place to get the deal over the line. This includes a restriction that it would not be allowed to sell Sky News for 15 years without the consent of the Secretary of State, would need to formally preserve the independence of the news broadcaster and would need to increase Sky News’ budget to at least £100M per year. The consultation process for these undertakings closed last week and are expected to be made public in the next few days.

Then we’ll get into an old-fashioned financial battle for the ownership of the pay-TV operator, which has satellite pay businesses and OTT services in the UK and Ireland, Germany and Austria and Italy. While the billion dollar interest in the business has largely been based around Sky’s eyeballs, and its loyal customers that are willing to spend hundreds of dollars per month for a range of services, the Osterley-based company also owns stakes in a number of other businesses including a raft of production companies, distribution entities and digital firms.

The fight between 21st Century Fox and Comcast could lead to bids of up to £15 or £16 per share, which values Sky at between $35B and $37B.

All of this comes as Comcast is thought to be preparing its own bid to buy 21st Century Fox. The Brian Roberts-run firm could make a counteroffer this week after Disney raised its offer from $52.4B to $71.3B.