Hamish Marshall walks out on New Zealand

Hamish Marshall has dropped a bombshell on New Zealand, refusing a national contract for 2007-08 so he can play county cricket as a Kolpak player. The decision means Marshall's international career is on hold indefinitely, as he cannot represent New Zealand while he is classified as a local player in England.

However, he has not ruled out a return to New Zealand in the coming years. Marshall said his decision was based on securing his financial future. "This has been the most difficult decision of my life," he said. "I have been extremely proud to represent my country during the last six years and have thoroughly enjoyed every moment of my time in the Blackcaps."

Marshall, 28, is currently registered as an overseas player with Gloucestershire but he carries an Irish passport, meaning he can remain as a local player. He has not played Test cricket since the tour of South Africa last April and was a late addition to New Zealand's World Cup squad, where he featured in three matches and scored one half-century.

His decision means New Zealand can now decide on a replacement in their national squad, raising the intriguing possibility that Mathew Sinclair could be reinstated after losing his contract and considering a move overseas. The team's general manager, Lindsay Crocker, said Marshall's replacement would be announced next week.

"I spoke to Hamish about the decision earlier today," Crocker said. "I believe he likely had a future with the Blackcaps, however I accept his reasons for pursing the certainty of a career in county cricket and wish him all the best."

Marshall said he owed a debt of gratitude to John Bracewell and the rest of New Zealand's off-field staff for the opportunities he had received. "They have created an excellent team environment that I have found very difficult to leave," he said.

"I would also like to acknowledge the support I have had from my [New Zealand] team-mates, who it has been a pleasure to play alongside. This has not been an easy decision but I now look forward to the future and hope that I will still have opportunities to play in New Zealand before my career finishes."

Marshall first appeared on the international scene in 2000-01, when he made his Test debut in Johannesburg aged 21. He has played 13 Tests and made 652 runs at 38.35. His two Test centuries both came at home within the space of a month in 2004-05. The first was an impressive 146 against Australia at Christchurch and the second was 160 in a high-scoring draw with Sri Lanka at Napier.

He was more often used as a limited-overs player but he never quite matched the brilliance of his first overseas tour in 2003-04, when he averaged 81 and scored his only ODI century, an unbeaten 101, in a five-match series in Pakistan. From 66 ODIs, Marshall has made 1454 runs at 27.43, but he has reached 50 only twice from his last 30 innings.