(Sharecast News) - London's FTSE 100 was down 0.8% at 8,296.96 in afternoon trade on Tuesday.

Ashtead rallied after it posted a drop in first-quarter profit that was in line with market expectations.

Russ Mould, investment director at AJ Bell, said: "Ashtead's first-quarter results are not particularly flashy, but the absence of any further profit warnings is giving the shares a lift, as profit momentum seems to be bottoming out".

Rolls-Royce also gained, having slumped on Monday when it was hit by news that Cathay Pacific had temporarily grounded its fleet of A350 aircraft for inspections after discovering problems with its RR engines.

Cathay Pacific said on Tuesday that three of the 48 Rolls-Royce-powered planes it had inspected had been successfully repaired and all of the jets were set resume operation by Saturday.

Mould said the rebound in the share price "isn't guaranteed to last, particularly as there is still a lack of detailed information on the incident and how many other engines might be affected".

He added: "Another scandal could scupper Rolls-Royce's recovery efforts. A lot of people will remember the company's previous crisis involving its Trent 1000 engines, which damaged the British engineer's reputation and led to significant extra costs.

"Since then, it has worked tirelessly to get back on track while also trying to make the business run more efficiently and operate in a leaner way.

"It has enjoyed considerable share price gains in the past few years and investors will be keeping their fingers crossed that the Cathay Pacific incident is an isolated one. Given this is still a fluid situation, shareholders need to brace themselves for more share price volatility."

Hikma Pharmaceuticals advanced after an upgrade to 'buy' from 'hold' by Berenberg, which hiked the price target to 2,400p from 2,100p as it said "clear progress" had been made.

"We have more confidence in the growth outlook across the business (including the US Generics business) for the next year and we also have more certainty on the business's leadership, following a period of management change - this included the hiring of a new permanent CEO (an internal appointment who knows the business well), as well as a new head of Injectables and US Generics," the bank said.

Rightmove was in the red, having surged on Monday after Australian real estate advertising company REA Group confirmed speculation that it was considering a possible cash and share offer for UK property platform.

FTSE 100 - Risers

Ashtead Group (AHT) 5,508.00p 2.80%

Rolls-Royce Holdings (RR.) 477.20p 2.78%

Tesco (TSCO) 361.60p 1.54%

B&M European Value Retail S.A. (DI) (BME) 443.20p 1.30%

Hikma Pharmaceuticals (HIK) 1,993.00p 0.96%

Intertek Group (ITRK) 4,950.00p 0.90%

Marks & Spencer Group (MKS) 342.70p 0.82%

Diploma (DPLM) 4,456.00p 0.77%

Severn Trent (SVT) 2,581.00p 0.70%

easyJet (EZJ) 478.20p 0.67%

FTSE 100 - Fallers

Rightmove (RMV) 670.60p -5.28%

Glencore (GLEN) 387.00p -3.18%

Fresnillo (FRES) 525.00p -3.14%

Melrose Industries (MRO) 471.10p -3.03%

Anglo American (AAL) 2,151.50p -2.87%

Antofagasta (ANTO) 1,792.50p -2.71%

BP (BP.) 420.05p -2.37%

Shell (SHEL) 2,629.00p -2.07%

NATWEST GROUP (NWG) 335.90p -2.04%

Intermediate Capital Group (ICG) 2,074.00p -1.98%