(Sharecast News) - London's FTSE 100 was up 0.6% at 10,650.97 in afternoon trade on Friday.
Engine maker Rolls-Royce and BA and Iberia owner IAG racked up strong gains as oil prices tumbled on Friday after Iran said the Strait of Hormuz is now "completely open".
The country's foreign minister, Abbas Araghchi, said in a social media post: "In line with the ceasefire in Lebanon, the passage for all commercial vessels through Strait of Hormuz is declared completely open for the remaining period of ceasefire."
However, he said vessels must transit through a "coordinated route" announced by Iran's maritime authorities.
Intertek continued to rise, having surged on Thursday after saying it rejected a 5,150p per share takeover proposal from Swedish private equity firm EQT.
On the downside, SSE and British Gas owner Centrica both tumbled after Chancellor Rachel Reeves said her and energy secretary Ed Miliband were looking at ways to break the link between electricity and gas prices.
Oil giants BP and Shell suffered heavy losses on the back of sliding oil prices.
FTSE 100 - Risers
Rolls-Royce Holdings (RR.) 1,317.40p 5.82%
International Consolidated Airlines Group SA (CDI) (IAG) 405.60p 5.49%
Intertek Group (ITRK) 5,012.00p 5.19%
ICG (ICG) 1,875.00p 4.80%
Melrose Industries (MRO) 563.60p 4.62%
Burberry Group (BRBY) 1,181.40p 4.42%
Persimmon (PSN) 1,208.00p 4.31%
InterContinental Hotels Group (IHG) 145.80p 4.25%
3i Group (III) 2,903.00p 4.24%
SEGRO (SGRO) 741.40p 4.16%
FTSE 100 - Fallers
SSE (SSE) 2,440.50p -7.18%
Centrica (CNA) 193.85p -6.74%
BP (BP.) 546.70p -6.49%
Shell (SHEL) 3,215.50p -5.26%
Vodafone Group (VOD) 112.70p -3.05%
BT Group (BT.A) 215.25p -2.20%
Glencore (GLEN) 542.90p -2.08%
Tesco (TSCO) 483.85p -1.99%
Imperial Brands (IMB) 2,747.00p -1.57%
National Grid (NG.) 1,269.40p -1.57%