Great Britain will face second seeds Croatia or Hungary in the Fed Cup promotion play-off on Saturday.
Their place was confirmed after Lativa beat Portugal in Britain's group, confirming that Anne Keothavong's team will top Group C.
It means that Britain no longer have to win their ongoing match with Turkey.
Heather Watson powered Great Britain to a 1-0 lead in their final best-of-three match with Turkey, beating 163rd-ranked Ipek Soylu 6-0 6-1.
British number one Johanna Konta she takes on world number 86 Cagla Buyukakcay in the second singles match.
Unlike the men's team competition, the Davis Cup, which has a World Group of 16 nations, the Fed Cup divides its top teams into two groups of eight - World Group I and World Group II.