British telecoms giant BT Group has been hit with a bill of around 350 million pounds in fines and compensation following delays to high-speed cable installations by its broadband unit, a watchdog said today. BT has been fined a record 42 million pounds (39 million euros) and must compensate rivals by around 300 million pounds for a "serious breach of rules," Ofcom said in a statement. The breach concerns work carried out by its Openreach unit, which BT earlier this month agreed to legally separate to remedy concerns over competition in the UK telecoms sector. Created by BT in 2005, Openreach maintains tens of millions of copper and fibre lines connecting telephone exchanges to homes and businesses across the UK - giving it a competitive advantage over rivals. Also watch:\u00a0[jwplayer LCiBNmxK] Ofcom's Investigations Director Gaucho Rasmussen said in a statement Monday: "We found BT broke our rules by failing to pay other telecoms companies proper compensation when these (installation) services were not provided on time. "The size of our fine reflects how important these rules are to protect competition and, ultimately, consumers and businesses. Our message is clear - we will not tolerate this sort of behaviour."