FTSE 250 movers: Tullow gushes higher on Guyana discovery; Sirius slides

London's FTSE 250 was down 0.7% at 18,959.85 in afternoon trade on Monday.

Tullow Oil was the standout gainer after the oil and gas exploration group said it had made a "substantial and high value" oil discovery in Guyana.

The stock was also boosted by an upgrade to 'buy' from 'hold' at Berenberg, which said the discovery at the Jethro field offshore Guyana and the subsequent de-risking of exploration potential in the Orinduik block address one of the key problems of Tullow Oil’s investment thesis - portfolio depth.

Acacia Mining was on the front foot as it said it can now resume gold exports from its North Mara mine in Tanzania after receiving government clearance. The ban was introduced in 2017 to keep processing activities in Tanzania.

On the downside, Sirius Minerals was under the cosh again following news last week that it had pulled a $500m bond offering that was crucial to the funding of its Woodsmith mine due to "market conditions".

Intu Properties was in the red as RBC Capital Markets slashed its price target to 43p from 100p. It pointed to broad-based weakness in the company's first-half results versus its expectations, ongoing deterioration in sentiment towards UK retail property and significant macro uncertainty and said it was making "large negative revisions" to its forecasts.

Shipping services company Clarkson lost ground even as it posted a small rise underlying interim pre-tax profits and said it expects a pick-up in the second half.

RHI Magnesita retreated despite reporting a jump in first-half profit amid difficult end markets.

FTSE 250 - Risers

Tullow Oil (TLW) 213.80p 19.37%
Funding Circle Holdings (FCH) 128.00p 3.72%
Acacia Mining (ACA) 250.82p 2.29%
Serco Group (SRP) 141.40p 1.43%
Polymetal International (POLY) 1,075.50p 1.41%
Cairn Energy (CNE) 161.60p 1.38%
Hikma Pharmaceuticals (HIK) 1,978.50p 1.28%
Rank Group (RNK) 162.00p 1.25%
Vivo Energy (VVO) 117.40p 1.21%
AJ Bell (AJB) 386.50p 1.18%

FTSE 250 - Fallers

Sirius Minerals (SXX) 8.10p -12.53%
Intu Properties (INTU) 34.34p -6.74%
Metro Bank (MTRO) 280.40p -6.16%
Clarkson (CKN) 2,370.00p -6.14%
RHI Magnesita N.V. (DI) (RHIM) 3,984.00p -4.28%
Quilter (QLT) 130.25p -4.09%
CYBG (CYBG) 148.40p -4.01%
Provident Financial (PFG) 371.40p -3.78%
Mediclinic International (MDC) 309.20p -3.34%
TP ICAP (TCAP) 270.90p -3.25%