HARARE, Zimbabwe (CNN) -- Zimbabwe President Robert Mugabe's government has issued a new passport to opposition leader Morgan Tsvangirai, according to a senior official with Tsvangirai's Movement for Democratic Change party.
U.S. envoy said viable unity government is impossible while President Mugabe remains in power.
Tsvangirai had threatened to pull out of a power-sharing deal with Mugabe unless the passport was issued.
"He now has the document after a long struggle," said the MDC official, confirming a report in the state-owned weekly The Sunday Mail.
Tsvangirai is in neighboring Botswana, but has said he cannot return to Zimbabwe without a valid passport.
Party spokesman Nelson Chamisa would not comment on whether the passport was issued.
Asked whether Tsvangirai would join Mugabe's government if given the passport, Chamisa said it was more important that Mugabe's ZANU-PF party "shows sincerity by releasing the people it abducted and resolves the outstanding issues of equitable distribution of cabinet and senior posts" in the government.
Tsvangirai and Mugabe signed the unity deal September 15, but Mugabe's ZANU-PF party and the MDC have failed to implement it because they cannot agree on who should control key ministries.
Last week, Jendayi Frazer, U.S. assistant secretary of state for African affairs, said the United States felt a viable unity government would not be possible as long as Mugabe remained in power.
Under the agreement, Tsvangirai would become prime minister. He had not been granted a new passport since his previous one expired last year, however, and has been using emergency travel documents to travel.
Tsvangirai said earlier this month he would pull out of the power-sharing pact unless he received a new passport and 32 detained opposition members were released.
The 32 -- who include a 2-year-old child -- remained in police custody Sunday, however, while government lawyers challenged a High Court order issued earlier this week ordering their release.
In October, Mugabe spokesman Charamba said that the delay in issuing Tsvangirai with a new passport was "because Zimbabwe is running out of paper for passports ... because of sanctions" imposed on the regime by the West. Mugabe accuses Tsvangirai of having campaigned for the sanctions.
The MDC leader has refused to form the government of national unity with Mugabe, accusing him of taking all key cabinet ministries such as home affairs, local government, information, foreign affairs and defense.