BT Group has signed a television partnership with 'Game of Thrones' producer HBO Home Entertainment whereby customers can download programmes 'for keeps'.All episodes of HBO programmes, including the first four Game of Thrones seasons, comedy series Entourage and crime drama True Detective, shown on BT TV's set-top boxes will be automatically available for customers to watch on their smartphones, tablets or PCs at no extra cost.After BT's plunge into televised sport since 2013, which in March saw it commit to an investment of £960m in securing English Premier League football rights, the HBO deal represents another step by the company into rival Sky's territory.Sky has had exclusive rights to show most of HBO's output in the UK, enjoying the enormous popularity of Game of Thrones, a fantasy series based on the books of George RR Martin.With this new deal, BT has become the first pay TV provider in the UK to offer customers the chance to buy-to-keep the box set of Game of Thrones and other HBO programmes.BT TV director Alex Green said: "This is yet another fantastic first for our customers. We are committed to offering the widest choice of on demand and live content, with pricing and flexibility to suit all our customers."The new deal with HBO comes at the perfect time for people who want to catch up with world-class TV shows over the long Bank Holiday weekend. But of course you get to keep them so you can watch over and over again."Sofia Chang, executive vice president and general manager, HBO Home Entertainment, said: "We are excited to extend our digital footprint in the UK by making our content available to BT TV customers. More and more fans are looking to own their favourite programmes digitally and this is another step for HBO Home Entertainment to expand its reach in this important market."