UPDATE 2-FTSE 100 lower as demand worries weigh on oil majors

* FTSE 100, FTSE 250 down 0.2%
* China's outlook weighs on oil and gas firms
* Trade tensions, Brexit uncertainty curb risk sentiment
* GSK rises after ovarian cancer study results

(Adds news items, updates to closing prices)
By Yadarisa Shabong and Shashwat Awasthi
Sept 30 (Reuters) - Britain's FTSE 100 index closed lower on
Monday, weighed by oil majors as concerns over global growth
resurfaced due to a weak economic outlook for the world's
largest crude importer, China, amid simmering trade tensions
with the United States.
The exporter-heavy FTSE 100 index .FTSE fell 0.2%,
slightly off its near two-month high, and the mid-cap FTSE 250
index .FTMC dropped by the same margin.
Shell RDSa.L and BP BP.L were the biggest drags on the
main bourse, tracking a fall in crude oil prices. O/R
Still, the FTSE 100 index had its best month since June,
bouncing back from losses in August that were triggered by
escalating trade jitters and accompanying fears of a global
recession, as well as sustained Brexit anxiety. The
domestically-focussed FTSE 250 registered its biggest monthly
rise since April.
On a quarterly basis, the main bourse was marginally down,
while the mid-cap index enjoyed its third consecutive quarter in
positive territory.
GlaxoSmithKline and AstraZeneca both reported trial results
on Saturday that will likely make their competing drugs
available to a wider group of ovarian cancer patients, possibly
helping GSK catch its rival in a highly contested drug class.
Shares of GlaxoSmithKline GSK.L rose 1%, while and
AstraZeneca AZN.L dipped 1.7% after nine consecutive sessions
in the black.
Global miners .FTNMX1770 also contributed to the session's
losses with a 1% fall as sentiment around U.S.-China trade
remained uneasy.
White House trade adviser Peter Navarro on Monday dismissed
reports that Washington was considering de-listing Chinese
companies from U.S. stock exchanges.
With just a month left until Britain is scheduled to leave
the European Union, there was very little action on the Brexit
front and market participants were left waiting for what may
happen next in Britain's already chaotic Brexit process.
"Investors have two of the horsemen front and centre this
week - it's a case of trade tensions ad nauseum, Brexit ad
infinitum," Markets.com analyst Neil Wilson said.
Among individual stocks, Premier Inn owner Whitbread
WTB.L dropped 3.9% after Barclays downgraded it to 'equal
weight', saying it sees more downside than upside risks.
Small-cap Metro Bank MTRO.L added 3.8% after a report that
activists led by Elliott Advisors were mulling taking a stake in
the lender.
Mid-cap HomeServe HSV.L rose up 1.8% after RBC raised its
rating and nearly doubled its price target on the home repairs
provider, while Sirius Minerals SXX.L more than recouped
losses seen last week with a 37% jump.