LONDON, May 24 (Reuters) - Britain is urgently investigating reports that cluster munitions made in the country had been used by a Saudi-led coalition in Yemen, foreign minister Philip Hammond told parliament on Tuesday.

A report published by Amnesty International on Monday said it had documented the use of cluster bombs in Yemen that had been manufactured in Britain in the 1970s.

"The MoD (Ministry of Defence) is now urgently investigating the allegations that have been made," Hammond told parliament. He said the weapons described in the report were decades old, and that it was now illegal to supply such bombs under British law.

Hammond said that there was currently no evidence that Saudi Arabia had used cluster munitions, and that Britain believed it had been given assurances from Saudi authorities that such weapons had not been used.

(Reporting by William James; Editing by Andrew Heavens) ((stephen.addison@thomsonreuters.com; 0207 542 7947;))