LONDON (Reuters) – Bank of England Chief Economist Huw Pill said on Friday that interest rates would remain the main monetary policy tool for the central bank as it prepares to start selling bonds acquired as part of its economic stimulus efforts. Pill said in a speech to the Walter Eucken Institut in Germany that selling assets, known as quantitative tightening (QT), would help to tighten monetary policy. “But as long as we undertake any gilt sales programme in a gradual, predictable and well-communicated manner in a reasonably benign market environment, we can still use Bank Rate as the marg…