Javier Solana, the EU's foreign policy chief, on Tuesday urged rival Palestinian factions to stop fighting and end the chaos in the Gaza Strip that threatens to unravel the Palestinian unity government. "The situation of security is very serious and we would like that to be controlled," Solana told reporters after talks with Palestinian Foreign Minister Ziad Abu Amr. "It will be very difficult to move forward politically if the situation internally among the Palestinians is not guaranteed." Solana rejected criticism the fighting was due to the international aid embargo the EU and other key donors like the US and the UN have imposed on the Palestinian government because it includes the militant Hamas group. The major donors have demanded that Hamas recognize Israel, renounce violence and commit to past agreements before aid is restored.