RAMALLAH, West Bank, April 20 (Reuters) - A spokesman for Mahmoud Abbas denied a newspaper report on Tuesday that the Palestinian president was suffering from a heart complaint.

Reports about the president being ill are not true. The president is in good health, spokesman Nabil Abu Rdainah said by telephone from Egypt where Abbas was holding meetings.

Other Palestinian officials, speaking anonymously, said Abbas had been suffering from back pain since falling during a visit to Tunisia last month. But they also denied that the 75-year-old, Western-backed leader was seriously ill.

Al-Quds al-Arabi newspaper, published in London, quoted unnamed sources on Tuesday as saying Abbas had heart problems.

Abbas became president of the Palestinian Authority, based in the Israeli-occupied West Bank, and leader of the dominant Fateh movement within the Palestine Liberation Organization (PLO) after the death of Yasser Arafat in late 2004.

His presidential term should have expired, triggering new elections, but the schism between the PLO and the Islamist Hamas movement, which seized the Gaza Strip from Abbas's forces in 2007, has left the constitutional processes in limbo. The PLO, of which Hamas is not a member, has extended Abbas's term.

Abbas has said he will not seek a renewal of his mandate.

No clear successor has emerged from Fateh's ranks.

Some indications of shifting power balances may come from a reshuffle of Prime Minister Salam Fayyad's cabinet, which officials said on Tuesday was likely within a couple of weeks. (Reporting by Mohammed Assadi and Ali Sawafta; editing by Alastair Macdonald)