Market players paid up to $4,500 per tonne to roll positions between the LME's cash and three-month contracts on Monday February 15, a record amount, while cash prices roared over 10-year highs and futures prices rose by a lesser degree.

While wide backwardations in the tin market are not uncommon, the exceptional divergence has forced the exchange to look closely at positioning and holdings, with executives holding calls with several key market players in recent weeks.

"The LME has been undertaking enhanced market monitoring for several weeks, and has further options available to ensure continued market orderliness if these are required," an exchange spokeswoman told Fastmarkets in a statement on Tuesday.

"The LME notes current tightness in the tin market. At present, there is no indication that LME pricing has diverged from the underlying physical market," she said.

Total LME tin stocks stand at 1,360 tonnes on Wednesday, with 1,235 tonnes on-warrant, following inflows this week including 550 tonnes delivered into Port Klang, Malaysia on Monday.

Low stock on the LME has been mirrored in the physical market, where premiums paid for spot tin have risen to unprecedented levels.

Fastmarkets’ tin grade A min 99.85% ingot premium, ddp Midwest US was $950-1,160 per tonne on February 9, up 69% since the end of last year when it was at $550-700 per tonne.