* VW says monitoring situation on metals markets

* Chipmakers WIN, TSMC, NXP see no immediate impact

* Fears China will also restrict rare earths exports

* U.S. Treasury Secretary Yellen visiting Beijing

TAIWAN, July 6 (Reuters) - Volkswagen said it is monitoring the situation on metals markets after China imposed export restrictions on two minor metals used in semiconductors and electric vehicles, while some chipmakers on Thursday played down the potential damage to supplies.

Fears are growing that more curbs on strategic exports including rare earths could be coming after a top Chinese trade adviser said on Wednesday that the limits on gallium and germanium, effective Aug. 1, were "just a start".

The abrupt announcement, days before Thursday's arrival in Beijing of U.S. Treasury Secretary Janet Yellen for a visit, sent some companies scrambling to secure supplies of the two metals and stirred concerns about a jump in prices.

It has also prompted more companies to re-think their reliance on the world's No. 2 economy.

VW, which relies on gallium and germanium for automotive products, said it was "ready to take measures together with its partners if necessary" but did not elaborate. The metals will also play a role in future autonomous driving functions, a spokesperson for the German carmaker said.

The export curbs are likely to further strain U.S.-China relations as the countries vie for dominance in semiconductor and defence technologies.

"If the talks between the two sides go well, many restrictions could be loosened, but if the talks go badly, both sides may put up more sanctions after Yellen goes home," said Capital Securities Corp analyst Liao Chien-yu.

Some industry players said the restrictions could leave China with a glut of the two metals, weighing on domestic prices even as costs overseas jumped this week.

Germanium is used in high-speed computer chips, plastics, and in military applications such as night-vision devices, as well as satellite imagery sensors. Gallium is used in radar and radio communication devices, satellites and LEDs.

Some larger chip manufacturers view China's export controls on gallium as more of a warning shot about what economic pain the country could inflict.

But if prices rise as restrictions take hold companies would have another reason to shift supply chains.

Taiwan's WIN Semiconductors, which uses gallium for optoelectronic devices, told Reuters only a "small number" of substrates are purchased from China, with most of its supplies coming from Germany and Japan.

Taiwan's TSMC, the world's largest contract chipmaker, said it does not expect any direct impact on its production from the moves.

Taiwan is a major producer of chips used in everything from smartphones and cars to fighter jets, supplying companies like Apple and Nvidia.

Chipmaker NXP Semiconductors sees no material impact on its business. NXP makes some chips for the auto and communications sectors using gallium or germanium.

(Reporting by Reuters bureaus; Writing by Josephine Mason; Editing by Catherine Evans)