  First measurements of the W -> lnu and Z/gamma* -> ll (l = e, mu) production
cross sections in proton-proton collisions at sqrt(s) = 7 TeV are presented
using data recorded by the ATLAS experiment at the LHC. The results are based
on 2250 W -> lnu and 179 Z/gamma* -> ll candidate events selected from a data
set corresponding to an integrated luminosity of approximately 320 nb-1. The
measured total W and Z/gamma*-boson production cross sections times the
respective leptonic branching ratios for the combined electron and muon
channels are $\stotW$ * BR(W -> lnu) = 9.96 +- 0.23(stat) +- 0.50(syst) +-
1.10(lumi) nb and $\stotZg$ * BR(Z/gamma* -> ll) = 0.82 +- 0.06(stat) +-
0.05(syst) +- 0.09(lumi) nb (within the invariant mass window 66 < m_ll < 116
GeV). The W/Z cross-section ratio is measured to be 11.7 +- 0.9(stat) +-
0.4(syst). In addition, measurements of the W+ and W- production cross sections
and of the lepton charge asymmetry are reported. Theoretical predictions based
on NNLO QCD calculations are found to agree with the measurements.
