CAIRO, Jan 10 (Reuters) - Egypt's Tourism Minister Hisham Zaazou said on Saturday that the government will announce additional security measures to safeguard tourists after an attack in the Red Sea resort of Hurgada left three injured on Friday.

Tourism is critical to the Egyptian economy as a source of hard currency, but has been ravaged by years of political turmoil since the revolution that ousted veteran president Hosni Mubarak in 2011.

"The welfare of the tourists visiting Egypt is of the greatest importance to us and will continue to be so.  No stone will be left unturned to ensure their security," Zaazou said.

"Over the coming days we will announce even greater security measures to safeguard all tourists visiting Egypt," he said.

Suspected militants armed with knives wounded two Austrian tourists and a Swede at a hotel in the Egyptian Red Sea resort of Hurghada on Friday evening.

Security forces shot and killed at least one of the attackers after they stormed the beachside Bella Vista hotel, officials said, though there was no immediate information on the other.

Security sources said the attackers had arrived by sea and also carried a gun and a suicide belt. Officials said officers had tightened checks across the area and shut off roads.

No group immediately claimed responsibility for the attack.

Germany updated its travel advice after the hotel attack, advising tourists in Hurghada not to go on any day trips from the resort for now and recommending they stay vigilant.

In response, the German arm of Europe's largest tour operator TUI said it was cancelling all day trips from Hurghada until the end of January.

It currently has about 3,100 German guests in Egypt, all of whom it said were fine. It said it would help those who wished to leave early, but that so far there had been only a few requests to return.

Egypt is fighting a wave of Islamist militancy and Islamic State claimed responsibility for the downing of a Russian passenger plane in October, killing all 224 people on board, most of them tourists returning home from the Red Sea resort of Sharm al-Sheikh, across the water from Hurghada.

Last month Egypt hired global consultancy Control Risks to review security at its airports after the crash but said it had found no evidence so far of terrorism or other illegal action linked to it. In November Russia said the jet was brought down by a bomb.

Islamic State said on Friday it had carried out an attack on Israeli tourists in Cairo on Thursday, in response to a call by the group's leader, Abu Bakr al-Baghdadi, to target Jews "everywhere".

Security sources said those tourists were Israeli Arabs.