  One "strong" magnetic cloud (MC) with the magnetic field magnitude reaching
$\sim$ 40 nT at 1 au during 2012 June 16-17 is examined in association with a
pre-existing magnetic flux rope (MFR) identified on the Sun. The MC is
characterized by a quasi-three dimensional (3D) flux rope model based on in
situ measurements from the Wind spacecraft. The magnetic flux contents and
other parameters are quantified. In addition, a correlative study with the
corresponding measurements of the same structure crossed by the Venus Express
(VEX) spacecraft at a heliocentric distance 0.7 au and with an angular
separation $\sim 6^\circ$ in longitude is performed to validate the MC modeling
results. The spatial variation between the Wind and VEX magnetic field
measurements is attributed to the 3D configuration of the structure as featured
by a knotted bundle of flux. The comparison of the magnetic flux contents
between the MC and the source region on the Sun indicates that the 3D
reconnection process accompanying an M1.9 flare may correspond to the magnetic
reconnection between the field lines of the pre-existing MFR rooted in the
opposite polarity footpoints. Such a process reduces the amount of the axial
magnetic flux in the erupted flux rope, by approximately 50\%, in this case.
