Washington  - The special US envoy for the Middle East, George Mitchell, has begun his second trip seeking to advance the Israeli-Palestinian peace process.

Mitchell arrived Tuesday in London for talks with British officials and will later head to Turkey, the United Arab Emirates, Egypt, Israel and the West Bank, State Department spokesman Robert Wood said.

In Sharm el-Sheikh, Wood said Mitchell will join Secretary of State Hillary Rodham Clinton to participate Monday in the donors conference for the rebuilding of the Gaza Strip, following the Israeli assault that ended in January.

The United States plans to pledge a "substantial" amount of money at the conference, but has not provided a figure, a US official said.

"We have made no decisions, and we are working across the government to determine what our approach will be," Clinton said Tuesday at a meeting with Spanish Foreign Minister Miguel Angel Moratinos. (dpa)