The FTSE 100 struggled on Thursday on a mixed day for stocks in London , and despite fresh falls in the oil price, as investors await fresh developments in the Middle East . “The wild streak of enthusiasm which hit markets amid hopes for a major de-escalation in the Iran conflict is tempering,” said Susannah Streeter, chief investment strategist at Wealth Club. “There’s a realisation that there are more hurdles to climb for a longer-term resolution to be agreed, even though Iran is reported to be studying a US peace proposal aimed at formally ending the conflict.” The FTSE 100 closed down 161.71 points, 1.6%, at 10,276.95. The FTSE 250 ended up 50.30 points, 0.2%, at 22,882.72, and the AIM All-Share rose 9.70 points, 1.2%, at 818.32. The oil price fell back amid continued hopes for a peace deal between the US and Iran. US President Donald Trump said an agreement could be near after positive talks, with Iran adding that it would pass on its latest position to mediator Pakistan.…