UK's FTSE 100 climbed on Thursday, tracking optimism in global markets amid encouraging signs on the U.S. debt ceiling discussions, while BT Group tumbled after the broadband operator reported weaker-than-expected cash flows.

BT Group Plc dropped 8.9% to a three-month low as the company reported annual cash flows for the year at the lower end of expectations, and said it expects to cut up to 55,000 jobs by 2030 as it completes its fibre roll-out and adapts to new technologies such as AI.

"It seems that after the COVID rebound, telecoms have not had enough to sell as a more interesting story," said Chris Beauchamp, chief market analyst at IG Group.

"There's clearly a lack of real strategy and it's not enough to just say we're going to cut costs. The question is what comes next."

Vodafone Group Plc earlier this week said it would cut 11,000 jobs globally over three years after it warned that a poor performance in its biggest market Germany would hit cash flow.

The blue-chip FTSE 100 rose 0.6%, reflecting an upbeat mood in global markets on hopes that Washington is edging closer to a deal to raise the U.S. debt ceiling and avert a default.

The midcap FTSE 250 added 0.4%, with Aston Martin jumping 10.5% after luxury carmaker said Geely Automobile Holdings Ltd would invest about 234 million pounds ($295.33 million).

UK's FTSE indexes have been trading in a tight range since late April as a mixed bag of corporate earnings and global angst over a possible U.S. debt default have weighed on sentiment.

Among other movers, luxury group Burberry Group Plc fell 6.2% as continued weakness in the United States overshadowed a stronger-than-expected fourth quarter sales driven by a rebound in China.

Premier Foods Plc climbed 5.7% after the maker of Mr Kipling cakes posted a strong annual profit and raised its dividend payout.

EasyJet Plc rose 1% after the airline posted a first-half loss in line with its guidance. (Reporting by Johann M Cherian in Bengaluru; Editing by Dhanya Ann Thoppil and Varun H K)