Two Israeli navy ships made a rare crossing of Egypt’s Suez Canal today, headed from the Mediterranean to the Red Sea a source at the port said.

One of the ships, the Hanit, already crossed the canal both ways in June, in what the source said was the first case of a large Israeli warship using the strategic waterway, although this was not possible to confirm officially.

After fighting several wars since Israel’s foundation in 1948, Egypt and Israel signed a peace treaty in 1979.

The other ship to cross today, the Eilat, was named after a destroyer sunk by Egypt with the loss of 47 lives shortly after the 1967 Arab-Israeli war, the source said.

It is thought that Israeli navy vessels did not previously use the canal for intelligence reasons, as they might be equipped with nuclear warheads that could be visible to the Egyptian authorities.

Israel is considered to be the Middle East’s sole, if undeclared, nuclear power. Israel’s Yediot Aharonot daily newspaper reported earlier this month that an Israeli submarine also used the Suez Canal for the first time in June, to reach military exercises in the Red Sea.

It said the Dolphin submarine’s crossing, escorted by Egyptian navy vessels, was intended as a message to arch-foe Iran.

Previously, Israeli submarines took weeks to round the whole of Africa to get to the Red Sea, with the paper saying “Egypt and Israel wanted to show their co-ordination in the face of Iran pursuing its nuclear programme.”

Israel suspects Iran of trying to build atomic weapons under the guise of a civilian nuclear programme, a charge Tehran has vehemently denied.