Blue chip shares touched a fresh mid-session record on Friday (2 June), before easing after losses among commodity stocks in afternoon trading.
The FTSE 100 Index lifted 22.1 points to 7565.8, after peaking at just one point under 7,600 in early morning trading. The FTSE 250 Index was 15.5 points higher at 20026.1.
Top flight shares cooled following a 1.8% fall in Brent Crude to $49.72, amid reports of increased oil production in Libya and the US. This left heavyweight oil stocks such as Royal Dutch Shell and BP 9.5p down to 2148.5p, and 3.8p lower at 477.3p, respectively.
Spreadex financial analysts Connor Campbell added: "Trump's decision to remove America from the Paris climate agreement has sparked concerns that the country will ramp up its drilling, negating any output cap implemented by the Organization of the Petroleum Exporting Countries [Opec]."
The biggest afternoon risers in the FTSE 100 Index were Old Mutual (+4.3p to 195p), Convatec Group (+7p to 337.7p), Carnival (+90p to 5125p), Standard Chartered (+12.4p to 757.2p) and International Consolidated Airlines (+9p to 611p).
The biggest afternoon fallers in the FTSE 100 Index were Antofagasta (-25.5p to 792p), Anglo American (-24p to 1010p), Marks & Spencer (-7.2p to 368.1p), United Utilities (-17p to 1005p) and Taylor Wimpey (-3p to 187p).
The biggest afternoon risers in the FTSE 250 Index were Acacia Mining (+8.8p to 292.3p), Dechra Pharmaceuticals (+57p to 1958p), Greencore Group (+6.2p to 248p), Rathbone Brothers (+63p to 2661p) and Metro Bank (+81p to 3800p).
The biggest afternoon fallers in the FTSE 250 Index were Ferrexpo (-5.6p to 170.8p), B&M European Value Retail (-10.5p to 360p), Polymetal International (-27p to 971p), Nostrum Oil & Gas (-13.5p to 505p) and Tullow Oil (-4.7p to 181.3p).