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TUNIS, July 30 (Reuters) - Tunisia has cut its 2015 growth forecast to 0.5 percent this year, down from an expected 1 percent, its finance minister said on Thursday, citing the "difficult situation" in its tourism sector after two major Islamist militant attacks.

Tourism revenues represent about 7 percent of the economy, and, adding to the decline, the country's vital phosphate exports have been disrupted by strikes and protests.

In 2014, Tunisia posted GDP growth of 2.3 percent.

Slim Chaker also told reporters that Tunisia would not be able to create a promised 40,000 jobs due to higher spending on combating terrorism, including boosting security forces.

Extra defence spending - taking the total to 306 million Tunisian dinars ($155 million) - would cut 20 percent off planned development expenditure, Chaker said.

Presenting a revised budget, he said total spending would fall in 2015 by 1.1 billion dinars, bringing down the deficit to 4.8 percent instead of the previously forecast 4.9 percent.

Last week, Tunisia's parliament approved a law allowing the death penalty for those convicted on terrorism charges.

Last month, a gunman killed 38 mostly British tourists in the Tunisian seaside city of Sousse. In March, two gunmen killed 21 foreign tourists and a policeman at Tunis's Bardo Museum. Both attacks were claimed by the Islamic State jihadist group.

The bill, which had been debated in parliament for years but put forward after the Sousse attack, will replace a law from 2003 which then-president Zine al-Abidine Ben Ali, toppled in a popular uprising in 2011, had used to crush dissent.

Tunisia has undergone a largely peaceful transition to democracy since its 2011 popular uprising. But its army has been fighting a rise in Islamist militancy.

The North African country is especially concerned about militants entering from neighbouring Libya, where Islamic State has established itself amid chaos caused by two rival governments battling for control and an ensuing security vacuum.

(Reporting by Mohamed Argoubi; Writing by Ulf Laessing; Editing by Louise Ireland) ((ulf.laessing@thomsonreuters.com; follow me on twitter @ulflaessing; Reuters Messaging: ulf.laessing.reuters.com@reuters.net))

Keywords: TUNISIA ECONOMY