The government has been in crisis since Prime Minister Morgan Tsvangirai began boycotting cabinet meetings.
Mr Tsvangirai is protesting at the way President Robert Mugabe is implementing the power-sharing deal.
Zimbabwean authorities are also under scrutiny at a meeting in
‘Unreliable partner’
Thursday’s talks by leaders of the Southern African Development Community (SADC) will include
Mr Tsvangirai and Mr Mugabe are also expected to attend. Former opposition leader Mr Tsvangirai has accused his long-time rival Mr Mugabe of being a "dishonest and unreliable partner" in the power-sharing deal, which was struck last year.
The opposition MDC party also accuses Mr Mugabe’s Zanu-PF party of persecuting its officials. Zanu-PF has described the accusations as "propaganda".
However, Human Rights Watch recently urged SADC leaders to press Zanu-PF to end what it called "ongoing human rights abuses".
Source: BBC News