June 1 (Reuters) - London copper ticked higher on Monday, supported by concerns over tightening supply and Goldman Sachs’ higher price forecast, though gains were capped by uncertainties over an Iran peace deal and slower factory activity in top consumer China.

The benchmark three-month copper CMCU3 on the London Metal Exchange rose 0.28% to $13,674.50 a metric ton as of 0310 GMT.

The most-active copper contract SCFcv1 on the Shanghai Futures Exchange slipped 0.07% to 104,770 yuan ($15,481.80) a ton. The Shanghai contract has been traded within a narrow range, gaining as much as 0.18% before nudging lower.

Concerns over global supply tightness continued to underpin copper prices, as Goldman Sachs on Monday raised its copper price forecast for the end of 2026 to $13,735 a ton from $12,465. The bank cited a tighter-than-expected market outside the U.S., with weak mine production growth globally.

Comex copper stocks HG-STX-COMEX rose more than 9% to 640,181 short tons (580,762 tons) through Friday, from April 14 when they first started to rise after a more-than-a-month long plateau, indicating a regional dislocation of copper is set to re-emerge between the U.S. and the rest of the world.

Goldman sees U.S. copper inventories increasing by around 900,000 tons this year, compared with an earlier estimate of 550,000 tons. Its base case, however, sees no U.S. copper import tariffs in 2026.

Meanwhile, investors continued to watch developments around Iran peace negotiations, with positivity connected to President Donald Trump saying he would soon decide on a ceasefire deal quickly offset by Israeli Prime Minister Benjamin Netanyahu's order for a deeper incursion into Lebanon to hit the Iranian-backed militant group Hezbollah.

China's slowing manufacturing activity also capped copper's gains. The official manufacturing Purchasing Managers' Index (PMI) stood at 50, the mark just separating growth from contraction in May, while a private survey showed a sixth straight month of expansion, though at a slower pace.

Among other LME metals, aluminium CMAL3 added 0.23%, zinc CMZN3 ticked 0.10% higher, lead CMPB3 was little changed, down only 0.02%, nickel CMNI3 dipped 0.25% and tin CMSN3 gained 0.36%.

Elsewhere on SHFE, aluminium SAFcv1 dipped 0.12%, zinc SZNcv1 lost 0.86%, lead SPBcv1 was also little changed, up only 0.03%, nickel SNIcv1 dropped 0.71% and tin SSNcv1 rose 0.48%.

($1 = 6.7673 Chinese yuan renminbi)