The City’s results season kicks off this week with figures from blue-chip firms including broadcast rivals BT and BSkyB and oil giant Royal Dutch Shell.

The battle between home communications giants BSkyB and BT will heat up with figures due from both firms amid reports that Sky is in talks over a tie-up with Vodafone to curb the power of its growing rival.

Sky Sports broadcster BSkyB has been left reeling after losing out on the UK rights to show Champions League and Europa League matches in November as BT continues to step up pressure.

BT, which updates on third quarter trading on Friday, agreed an exclusive deal worth almost £900million to show both UEFA competitions for three seasons from 2015/16 in a move marking the first time a single UK broadcaster has won the exclusive live rights for all 350 matches from the two tournaments per season.

But it is thought that Sky and Vodafone have been discussing ways to strengthen their defences against BT, possibly involving a deal on Sky’s sports and mobile channels and working together on a high-speed broadband service.

It comes ahead of BT’s joint venture with T-Mobile and Orange parent EE to launch a mobile phone service this year, which could be bundled with its other offerings in a so-called “quad play” package.

While the talks are said to be exploratory only, it shows how seriously the threat from BT is being taken in the market.

It launched BT Sport in August, which helped double the number of new broadband customers in the July to September quarter to 156,000 as many were lured in by a package including 38 top-flight football matches a season on its TV service.

It has pledged to make European football “far more accessible and affordable to fans”, and will show a selection of the games for free on BT Sport even to homes that have not signed up to the channels, although it does plan to introduce charging for the UEFA matches.

The group grew overall pre-tax profits by 2% to £609m in the second quarter, but analysts are pencilling in a slight dip in third quarter underlying profits to £672m from £675m a year earlier.

Simon Weeden, an expert at Citi, said while BT Sport had provided a boost to its broadband business, it has come at a hefty cost. He estimated BT would need to charge a 2m-strong customer base around £12.50 a month plus VAT to recover its UEFA rights costs, which followed hot on the heels of its £738m deal for 38 live Premier League matches.

“We see the cost of the UEFA football rights as disproportionately high for the value they will provide to BT and see the potential for financial risk as rights renewals come around, such as with the English Premier League,” said Mr Weeden.

Solid progress from BSkyB in its interims on Thursday is set to be overshadowed by its loss of prized football rights to BT, according to Numis Securities analyst Paul Richards.

“We expect more of the same operationally in the second quarter, with solid net additions in ‘traditional’ products and further very strong growth in connected services, which continues to be a key focus for Sky,” he said.

He is estimating 70,000 net additions for TV, 100,000 for HD and 75,000 for broadband, but this would be fewer than the 111,000 broadband customers added in the three months to the end of September.

Most analysts are pencilling in a 6% rise in half-year revenues to £3.8billion, but a fall in operating profits to £586m from £647m a year earlier as marketing and content costs weigh on results.

Royal Dutch Shell’s new boss Ben van Beurden will face tough questions over his turnaround plans when he presents annual results on Thursday, having issued a shock profits warning just two weeks after taking on the top job.

Mr van Beurden, who succeeded Peter Voser as chief executive on January 1, was forced to admit last year’s performance was “not what I expect from Shell” as he slashed expectations for the fourth quarter and full-year results.

The oil giant blamed the poor end to its year on a range of factors, including higher exploration costs, ongoing woes in refining and hefty writedowns relating to its upstream business.

It said fourth quarter earnings were now expected to plunge by 70% to around 2.2bn US dollars (£1.3bn) and 2013 earnings by 38% to about 16.8bn dollars (£10.3bn).

With writedowns stripped out, fourth quarter underlying earnings are now set to almost halve to around 2.9bn dollars (£1.8bn) and annual results fall by 23% to around 19.5bn dollars (£11.9bn). Analysts had been pencilling in fourth quarter underlying earnings of 4bn dollars (£2.4bn).

The profits alert came after an already difficult past few months for the Anglo-Dutch group, which disappointed the market last year when third quarter underlying profits slumped by a worse-than-expected 32%.

As with the entire oil industry, it has been suffering from low refining margins ? the amount of money that is made from processing crude oil into petrol and diesel ? and cautioned at the time of its third quarter figures that the last three months would also see the upstream business hit by higher maintenance fees.

But the profit alert and the scale of its guidance came as a surprise, as Shell very rarely issues warnings ahead of full-year figures.

Despite a fall of as much as 4% in the immediate aftermath of the announcement, shares only closed 1% down as the market saw it as an opportunity for the new chief executive to effect change.

Oil analyst Tony Shepard at Charles Stanley said: “The fourth quarter outcome may play into his hands giving him the opportunity to be more radical with his plans. Certainly, we expect a major step-up in divestments in 2014.”

Killik & Co experts added that despite more than 21bn dollars (£13bn) worth of assets being sold over the last three years, “a more substantial portfolio change is now called for”.

“If management take the view that there is no reason for an integrated oil major to really exist, then a lot of value could potentially be unlocked from a break-up,” he added.

Mr van Beurden will no doubt be quizzed over his initial thoughts on strategy for the group on Thursday, but all eyes will be on the group’s management and investor day on March 13 when he is likely to reveal more detailed plans.

Smirnoff vodka and Guinness giant Diageo reports half-year figures on Thursday amid a wave of optimism over sales to emerging markets after consumer goods group Unilever allayed fears of a slowdown with a stronger-than-expected end to its year.

Like Unilever, Diageo is a big seller into emerging markets and its shares responded well to news that its fellow FTSE 100 player had benefited from a rebound in key growth areas such as Russia, Turkey, China and Indonesia.

Diageo saw operating profits rise 8% in the year to June 30 thanks to strength in US spirits and continued double digit growth in emerging markets. Trading in the UK was also seen as resilient as strong sales of Smirnoff offset a weaker performance from Guinness.

A concerted marketing push helped increase its market share for a number of brands, in particular for scotch whisky, its biggest and most profitable category.

Full-year profits in North America rose 9% to £1.5bn, offsetting a fall of 9% to £656m in western Europe. Asia Pacific grew 21% to £414m, despite a second half slowdown in China as a result of an ‘’anti-extravagance’’ campaign launched by the government.

Analysts at Raymond James Euro Equities are pencilling in first half sales growth of 3.3% to £6.2bn after a slight pick up in the second quarter thanks to the Africa, Middle East, Eastern Europe region, while they predict underlying earnings will increase by 4% to £2bn.

But JP Morgan experts are concerned over the exposure of firms such as Diageo to China as the country’s clampdown on conspicuous consumption hits the premium spirits market.

“Consumption of high-end spirits has fallen by double digits in 2013 with some ultra premium segments completely wiped out,” they said. “The way forward remains murky, with the government’s stance not softening and the level of underlying demand for personal consumption still unclear.”

They estimate that around 2% of Diageo’s profit is generated from China.