Taiwan's Foxconn and TSMC said on Monday they had reached deals to buy 10 million doses of BioNTech SE's COVID-19 vaccine, putting the total cost of the highly politicized deal at around $350 million.

BioNTech's Chinese sales agent Shanghai Fosun Pharmaceutical Group Co. said on Sunday that an agreement had been signed, though the German firm has yet to comment and no details of a delivery time-frame have been revealed yet.

Foxconn's founder Terry Gou wrote on his Facebook page that he was "gratified" the deal had been completed, which will see Foxconn and TSMC each buy 5 million doses, to be donated to the government for distribution.

"But we can't relax, because we will continue to work hard to push for the delivery time and quantity," he said.

"However, this batch of vaccines delivered directly from the German factory I believe will help Taiwanese society to increase confidence and offer respite in the face of the epidemic."

Taiwan's government has tried for months to buy the vaccine directly from BioNTech and has blamed China, which claims the self-ruled island as its own territory, for nixing an agreement the two sides were due to sign earlier this year. China denies the accusations.

Last month, facing public pressure about the slow pace of Taiwan's inoculation program, the government agreed to allow Gou, as well as Taiwan Semiconductor Manufacturing Co. (TSMC), to negotiate on its behalf for the vaccines.

TSMC and Foxconn are major Apple Inc. suppliers.

Taiwan's government said it would comment later on Monday.

Gou said Beijing did not interfere in the talks.

"During the negotiation period after my donation was proposed, there was no guidance or interference from the Beijing authorities in the mainland on the vaccine procurement process."