Oil and gas services group Petrofac was the biggest riser on Monday, as share price increased by 3.6 per cent to 1,411p, after reporting a strong set of results.

The firm reported a 55 per cent surge in earnings before interest, tax, depreciation and amortisation of approximately £207 million ($321 million) during the first half of 2010.

Net profit rose by 128 per cent to around £214 million ($332 million) fuelled by the demerger of UK continental shelf specialist oil & gas subsidiary EnQuest.

Other big risers were insurance group Aviva as merger & acquisition speculation continues. The insurer saw share price rise by 3.3 per cent to 390p.

Financial services group Old Mutual reported a 3.1 per cent increase in share price to 124.7p after an earlier bid by HSBC for its South African-based banking subsidiary Nedbank.

Temporary power supplier Aggreko was the biggest faller in trading as share price dropped by 2.9 per cent to 1,464p.

Eurasian Natural Resources fell by 2.2 per cent to 849p as analysts reacted negatively to its acquisition late last week of Congolese mining company Camrose Resources for approximately £113 million ($175 million).

Investors reacted negatively to news that a firm which has a 70 per cent stake to a mining license in Kolwezi is disputed by Canadian firm First Quantum Minerals.

Global satellite communications firm Inmarsat's share price fell 1.9 per cent to 657.5p.