Jacques Kallis has been appointed as England's latest batting consultant for next month's Test series in Sri Lanka, a tour that the ECB insists is set to go ahead as planned in spite of the heightened uncertainty over the UK's latest wave of measures to tackle the Covid-19 pandemic.

The ECB last week stepped up its search for full-time appointments for their batting, pace- and spin-bowling coaching vacancies, with applications due to close on January 10, meaning that Kallis's appointment may be the last consultancy role used by the board. Similar appointments were made for Jonathan Trott during the Pakistan Tests last summer, and Marcus Trescothick on the recent white-ball tour of South Africa.

At this stage, Kallis is not expected to be involved in England's subsequent Test tour of India - although that may yet change, with the ECB having flagged the need to rotate their options for the foreseeable, to mitigate against the strain of living, practising and playing in bio-secure environments.

With that in mind, Graham Thorpe, England's regular assistant coach to Chris Silverwood, has been rested for this leg of the winter, but is expected to be back on board for the India tour. Jon Lewis, the former Gloucestershire and England seamer, travels as fast-bowling coach, while James Foster continues as wicketkeeping consultant in the wake of Bruce French's retirement last summer, as does Jeetan Patel as spin consultant.

However, it is Kallis's appointment which is the most eye-catching for the coming tour. He secured his status as an all-time great with 13,206 Test runs at 55.37 for South Africa, in addition to 292 wickets, while his mastery of Asian conditions is renowned, with eight centuries at 55.62 in 25 Tests in the region.

This time last year, Kallis was working as a batting consultant for South Africa's Test team during their 3-1 series loss against England. However, with CSA committing in September to a policy of affirmative action for future consultant roles, Kallis's opportunities for further work within his home country are limited, particularly now that the role of High Performance Batting Consultant, a position that spans all levels of the professional game in South Africa, has gone to his former team-mate Neil McKenzie.

Discussions between Kallis and the ECB are understood to have taken place earlier this month, and have been described as "very quick and simple". He is expected to link up with the squad when they travel to Hambantota on January 2, ahead of the first of two Tests against Sri Lanka in Galle starting January 14.

Concerns over the viability of the tour, which was belatedly confirmed by the Sri Lankan government earlier this month after protracted negotiations, have resurfaced this week given the extensive travel bans being imposed on the UK by several countries, following the spread of a new variant of the coronavirus.

That includes England's other new-year Test opponents, India, whose government has suspended UK flights as a temporary measure from December 22-31. England's squad are due to fly directly to India at the conclusion of their Sri Lanka tour on January 27.

ESPNcricinfo understands that a meeting is due to take place between Sri Lanka health authorities and those in the UK to discuss the implications of the latest Covid updates. However, given the financial importance of the England tour to Sri Lanka's finances, and the recent success of the Lanka Premier League, there is no suggestion yet that the tour is in peril.

An ECB spokesman told ESPNcricinfo: "We continue to plan as normal. We have regular meetings with Sri Lanka and there is another meeting planned for this week."