The theft of a Leonardo da Vinci painting from Drumlanrig Castle could result in multi-million pound claims against at least two specialist art underwriters.

Loss adjuster Mark Dalrymple of Tyler and Company said he was close to authorising payment of an undisclosed sum to the owner of Madonna with the Yarnwinder, the Duke of Buccleuch.

Though the level of insurance has not been disclosed, estimates put the cost of the painting between £15m and £70m, depending on whether the piece is a genuine da Vinci or painted by one of his students.

Hiscox fine art underwriter Daniel Wood said: "If it was worth £60m, the market is capable of withstanding it. But it may have an impact on profitability. For some time rates have been quite low as exposures have been low."

Insurers, who preferred to remain anonymous, have offered a six-figure sum as a reward for information leading to the picture's return.