Israel has cancelled a meeting with a visiting Norwegian minister after he held talks with the prime minister of the new Palestinian unity government.
Norway has eroded Hamas's isolation from Western countries
Norway was the first Western country to recognise the new government which contains members of the militant group Hamas and its main rival, Fatah.
Israel says it will not deal with the new administration, and has called for a continued international boycott.
The US and EU have withheld recognition but left a door open for future ties.
They say they will judge the government on its actions and meanwhile they have indicated they will maintain contacts with ministers who are not members of Hamas - which they consider a terrorist organisation.
Raymond Johansan, Norway's deputy foreign minister, had been due at the Israeli foreign ministry, but the meeting was called off.
On Monday, he met Prime Minister Ismail Haniya of Hamas and other government officials, becoming the first high-ranking Western official to visit leaders of the militant Islamic movement.
"This is standing policy," said an Israeli political source quoted by Reuters.
The source said Israel decided a year ago, after Hamas won parliamentary elections, it would boycott visiting dignitaries who met leaders of the group.
The US and EU want the new government to clarify its position in three areas, recognition of Israel, the armed struggle and signing up to past peace agreements.
The current platform talks of "respecting" peace deals, but also the "legitimate right" to all forms of Palestinian resistance, which US and EU say could include terrorist attacks on Israeli civilians.
Norway is not an EU member but has played a major role in past Middle East peacemaking.
In the 1990s, it hosted secret meetings between Israeli negotiators and members of the Palestine Liberation Organisation, which led to signing of the Oslo accords.