German Chancellor Angela Merkel welcomed the agreement between Berlin and Beirut and said she was satisfied with the rules of engagement for the employment of the German navy in the Middle East.

"We have achieved the essential," Merkel told reporters after a meeting with Spanish Prime Minister Jose Luis Rodriques Zapatero on Tuesday.

Lebanon is understood to have given a green light for German vessels to enter its waters in a bid to prevent arms being smuggled to the Hezbollah militia by sea, but Merkel did not offer any details.

Beirut had earlier insisted that the UN force's ships must stay seven miles (13 kilometres) from its coast, exasperating German politicians who argued that this would make the mission pointless.

Final decision pending

A government spokesman said the cabinet would now take a decision about Germany's contribution to the force on Wednesday.

Government sources said the Bundestag, or lower house of parliament, will start debating the mission next Tuesday and will vote on it before the end of next week.

Germany has offered to lead the naval component of the expanded UN force in Lebanon and is expected to contribute more than 2,000 soldiers. But the country's first military foray into the Middle East since World War II has been marked by confusion and delays.

Last week, Berlin was caught in a row between Israel and Lebanon about which should come first -- ending Israel's sea blockade of Lebanon or deploying German vessels.The blockade was lifted on September 8 and a UN-backed flotilla of French, Greek and Italian ships have begun patrolling the Lebanese coast on a temporary basis.

A security threat?

German conservative daily Frankfurter Allgemeine Zeitung (FAZ) reported on Tuesday that the German government offered to take a Lebanese officer on board the German command ship and consult him during the mission, although without granting him veto power.

This move, however, could pose a security problem for the German navy. According to FAZ, the Lebanese army does not use standard NATO equipment, which is why Lebanese officers could communicate with their command center only using open radio signals. Open radio signals emitted from German ships could potentially be intercepted by Hezbollah, which could put the German mission in danger.

If the German mission is approved, it is expected to take a further 10 days for the country's ships to reach Lebanon.