  We present a new mixed variable symplectic (MVS) integrator for planetary
systems, that fully resolve close encounters. The method is based on a time
regularisation that allows keeping the stability properties of the symplectic
integrators, while also reducing the effective step size whenever two planets
encounter. We use a high order MVS scheme such that it is possible to integrate
with large time steps far away from close encounters. We show that this
algorithm is able to resolve almost exact collisions (i.e with a mutual
separation of a fraction of the physical radius) while using the same time-step
as in weakly perturbed problem such as the Solar System. We demonstrate the
long term behaviour on systems of six super-Earths experiencing strong
scattering for 50 kyr. We compare our algorithm to hybrid methods such as
MERCURY and show that for an equivalent cost we obtain much better energy
conservation.
