Copper and aluminium fell on Friday as caution ​prevailed ahead of ⁠possible U.S.-Iran peace talks at the weekend.

Benchmark three-month copper on ‌the London Metal Exchange (LME) was down 0.5% at $13,209 a metric ton in official open-outcry ​trading but is up 3% this week after touching its highest since March ​2 at $13,392.50 ​on Wednesday.

Aluminium was down 0.4% at $3,630 a ton in official activity after hitting a four-year high of $3,672 in the ⁠previous session on expectations that the global aluminium market will face a supply deficit this year because of the Iran war.

U.S. President Donald Trump said the next meeting between the United States and ​Iran could ‌take place over ⁠the weekend, adding ⁠that he believed the U.S. was "very close to making a deal with Iran".

However, ​Iranian sources told Reuters that some "gaps remained to ‌be resolved" before a preliminary deal ⁠can be reached.

Strong prices for copper, aluminium and other metals drove the LME's index of six base metals contracts to a record high on Thursday on supply worries and investment from the wider financial system. Global equities were trading near record highs on Friday on the hopes for a peace deal.

Nickel rose 1.7% to $18,550 a ton after hitting $18,640 for its highest since January 29. Nickel ‌is up 7.7% this week, poised for its strongest ⁠weekly growth in two years owing to expectations ​of reduced supply after Indonesia revised its ore price formula.

Among other LME metals, zinc added 0.7% to $3,446.50 a ton after hitting $3,453 for its ​highest since ‌February 11. Lead gained 0.7% to $1,967 and tin ⁠lost 0.4% to $49,900.

(Reporting by Polina ​Devitt Additional reporting by Amy Lv Editing by David Goodman)