A Palestinian man who masqueraded as a Jew to have sex with a Jewish woman has been convicted of rape "by deception" and sentenced to 18 months in prison.

The unusual case underscores the racial tensions between Israel's Jewish and Arab communities, where intimate relations between the two are often regarded as taboo.

Sabbar Kashur, a 30-year-old delivery man, met the woman by chance in West Jerusalem, the Jewish sector, and within minutes of falling into conversation, they headed to a nearby office block to have sex. Mr Kashur told the woman, who has not been identified, that his name was Daniel to make her believe that he was Jewish, and that he was single and looking for a long-term relationship. It was only later that she learned he was Palestinian, prompting her to file charges of rape.

The woman initially accused Mr Kashur under oath of a brutal rape against her consent, a charge that carries a heavy jail sentence. But when Mr Kashur's lawyer mounted his own investigation and disproved her claims, the Jerusalem District Court agreed to a plea bargain.

"I wanted to prove the sex was consensual and I did so," said Adnan Aladdin, Mr Kashur's lawyer, adding that he planned to appeal.

Israelis, despite living side by side with Arabs in some parts of the country, often remain fiercely opposed to sexual liaisons outside of their own communities. Some organisations are entirely dedicated to "rescuing" Jewish girls from mixed-race marriages.

Mr Aladdin, a court-appointed lawyer, refused to be drawn on whether the court's verdict was racially motivated, saying only that he accepted a plea bargain rather than abandon his client to the mercy of the Israeli courts.

Explaining the court's decision, the Israeli judge, Tzvi Segal, wrote that it was not "a classical rape by force", but that consent was obtained under false pretences, Israel's Ha'aretz newspaper reported, citing court documents. "If she hadn't thought the accused was a Jewish bachelor interested in a serious romantic relationship, she would not have co-operated," Mr Segal wrote.

The case poses complex questions over when one decides that a deception has gone too far, such as in cases where a married man might claim that he is not married in a bid to elicit sex. Some would argue, however, that Mr Kashur is still guilty of a crime, even if no rape was involved. "If through the deception you make the other person act in a way they wouldn't without the deception" there is a criminal case to answer, said Moti Adato, an Israeli lawyer.

Some of the cases involving a charge of rape "by deception" have proved rather more elaborate. A Welsh woman accused a Syrian-born pilot of rape after he allegedly convinced her that the only way to treat a gynaecological infection was to have sex with him.