* FTSE 100 up 0.5%, FTSE 250 up 0.8%
* Markets seeing "classic squeeze" - analyst
* NMC enjoys best day ever
* Nichols slumps after profit alert
(Adds news items, analyst comments, updates to closing prices)
By Shashwat Awasthi
Dec 23 (Reuters) - Britain's blue-chip equities index gained
for a ninth straight session on Monday in holiday-thinned
trading, while midcaps hovered near all-time highs.
The FTSE 100 .FTSE rose 0.5% to hit its highest in nearly
five months and match its best run of gains since May 2017. The
FTSE 250 .FTMC jumped 0.8%, up for the third straight session.
Both benchmark indexes drifted lower in early dealings as
traders locked in profits ahead of Christmas, but a lack of
negative news and paltry trading volumes helped them recover.
"Given the low liquidity conditions, it does not take much
to change the market," Raymond James analyst Chris Bailey said.
"Note too the lack of real losers. Classic squeeze up just ahead
of Christmas."
The stand-out gainer was NMC Health NMC.L , which surged
almost 37% on its best day ever after it promised an independent
review of its books. Its shares had nearly halved in value last
week after short-selling firm Muddy Waters questioned its
finances. "The fact the company is taking such action implies they
don't have anything to hide, which has encouraged some traders
to swoop in and snap up the relatively cheap stock," CMC Markets
analyst David Madden said.
Dealers seemed content to reflect on major developments of
the month, including a breakthrough in U.S.-China trade talks
and UK Prime Minister Boris Johnson's election victory which
have helped the FTSE 100 surge nearly 5% in the last two weeks.
The exporter-heavy index is on course for its best month
since June, while the more domestically-focussed midcaps are on
track for a fourth straight month of gains. Both benchmark
indexes look set for their ninth month of gains this year.
Some of that momentum has eased after Johnson's hard line on
a trade agreement with the European Union revived fears of a
chaotic Brexit and market players are likely to hold off on
making further bets before the new year.
Lingering Brexit concerns left sterling hamstrung on Monday,
boosting firms with a larger international exposure such as
Shell RDSa.L , Unilever ULVR.L and Diageo DGE.L , which lent
further support to the main index.
Other news-driven moves saw AIM-listed Nichols NICL.L drop
10% to its lowest since Jan. 3, after the Vimto soft drinks
maker warned on its 2020 profit.