Trading at the Pakistan Stock Exchange (PSX) turned mildly negative on Tuesday as profit-taking erased early gains after the morning rally, although buying in index-heavy stocks continued to provide support amid optimism over a possible resolution to the United States-Iran conflict.

The benchmark KSE-100 Index stood at 171,107.46 at 12:43pm, down 45.70 points or 0.03% from the previous close of 171,153.16.

The market had opened on a positive note, with the index rising 381.37 points, or 0.22%, to 171,534.53 by 9:38am as investors anticipated developments at the United Nations that could help end the US-Iran conflict.

Index-heavy stocks from key sectors including automobile assemblers, cement, commercial banks, oil and gas exploration companies, power generation and refineries, kept buying momentum alive during the morning session.

Read: PSX rises 269 points as oil market steadies

However, profit-taking emerged later, with the index touching an intraday high of 171,680.73 and a low of 171,049.09.

Meanwhile, oil prices rose for the first time in five sessions as investors awaited developments on potential US-Iran talks at the UN General Assembly this week, while more supplies emerged through the Strait of Hormuz over the weekend.

By midday, 59.43 million shares had changed hands with traded value standing at Rs3.31 billion.