The chairman of the Alliance Boots pension scheme has written to MPs seeking their support in talks with US private equity firm Kohlberg Kravis Roberts.

“We should welcome any help and support you might be able to provide to ensure that this unsatisfactory period of uncertainty for our members is concluded as quickly as possible,” the trustees’ chairman John Watson wrote in a letter seen by The Times.

Representatives of KKR and the trustees of the scheme, which has more than 66,000 members, remained in talks yesterday and further meetings are scheduled for today and tomorrow.

The trustees have been unable to reach a deal with the American private equity firm, which is financing the deal with £8.2 billion of debt, over the handling of Boots’s £305 million pension fund deficit.

Sources said that a deal could be struck before the end of the week although “material differences” still remain between the two sides.

In his letter to MPs, Mr Watson said that he was “very concerned that we have not been able to reach agreement with KKR and Mr Pessina [Boots’ deputy chairman], particularly as the proposed acquisition has now been approved”.

Lawyers for the Boots fund have advised trustees that they could use a June 21 court hearing that is due to approve a takeover by KKR as a last-ditch opportunity to block the deal.

KKR, and its partner Stefano Pessina, have offered the scheme a package totalling £940 million but the two sides remain split over the amount of cash required upfront and the timetable for further payments.

The private equity firm is understood to have suggested establishing an emergency fund of £600 million and then paying £340 million into the scheme over a decade. The trustees are thought to be seeking about £100 million more than they have been offered.

Terry Rooney MP, chairman of the Parliamentary Select Committee on work and pensions, is understood to be concerned about the Boots scheme.

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