Tullow Oil has downgraded its 2019 output guidance to 90,000-98,000 barrels of oil per day (bpd) due to problems at its Ghana fields.
But the exploration company said it sees final go-aheads for its Uganda in the second half while its Kenya project timeline was "ambitious".
"Ghana's performance was below expectations due to gas compression constraints on Jubilee during February and a delay in completing the Enyenra-10 production well at the TEN field. Both issues have now been resolved," Tullow said today.
It had previously expected to produce between 93,000 and 101,000 bpd.
With much focus on Tullow's three-well drilling programme offshore Guyana, this year is also crunch time for its East African projects.
Final investment decisions for its Ugandan project had been planned around mid-year and Kenya by the end of the year, which Tullow called "an ambitious target" today.
The shipment of a first cargo of Kenyan oil to test the market, which was originally planned in the first half as well, is expected to sail in the third quarter, Tullow said.
In Uganda, a $208m payment after selling a stake in its onshore fields to Total in a so-called farm-down deal was delayed last year because the country asked for more tax on the deal than expected.
"These discussions are expected to conclude shortly and will enable completion of the farm-down," Tullow said.
The company said it has reduced its debt from $3.1 billion at the end of 2018 to $3 billion at the end of March.
It has hedged 56,000 bpd this year at a floor price of $56.40 a barrel and 31,000 bpd at $58.68 a barrel for 2020.