UPDATE 2-London stocks sink amid Sino-U.S. tensions, mark weekly losses

* FTSE 100 marks worst week in six
* Insurers weigh as coronavirus relief measures extended
* Centrica surges on North American energy business sale
* GVC Holdings underperforms for the week

(Updates to close)
By Sagarika Jaisinghani and Ambar Warrick
July 24 (Reuters) - British shares fell on Friday as souring
U.S.-China relations weighed and marked weekly losses as
concerns over the coronavirus and uncertainty over a vaccine
spurred a selling-out of equities.
The blue-chip FTSE 100 .FTSE ended down 1.4%, with all
sectors trading in the red. The index fell 2.6% for the week.
Major insurers Prudential PRU.L and M&G PLC MNG.L
weighed as Britain's markets watchdog said it was proposing to
extend temporary relief measures to help insurance customers
facing difficulties due to the coronavirus pandemic until the
end of October. The mid-cap FTSE 250 .FTMC shed 1.3%, and edged lower for
the week.
Sentiment was hurt as Beijing ordered the United States to
close its consulate in Chengdu, in retaliation for being told to
shut its consulate in Houston earlier this week. MKTS/GLOB
"The big question remains: for how long can the bulls hold
on to the driver's seat," said Charalambos Pissouros, market
analyst at JFD Group.
"Further escalation in U.S.-China tensions and a second
round of lockdown measures may force more market participants to
abandon equities and other risky assets."
The FTSE 100 has struggled in July to build on a three-month
rally as hopes for a stimulus-led economic rebound were dented
by surging global COVID-19 cases and relatively bleak corporate
forecasts.
Ladbrokes owner GVC Holdings GVC.L underperformed its
peers on the FTSE 100 for the week as British tax authorities
expanded an investigation into the gambling company's former
online business in Turkey. Gold miner Polymetal POLYP.L outperformed its blue-chip
peers for the week after clocking higher quarterly production,
while also benefiting from higher bullion prices. GOL/
In Britain, retail sales jumped back almost to
pre-coronavirus lockdown levels in June when non-essential
stores in England reopened, but analysts warned that a greater
shift toward online shopping might prevent a V-shaped recovery.
British Gas owner Centrica Plc CNA.L surged more than 16%
after it announced plans to sell its North American subsidiary
Direct Energy for $3.63 billion.