• The yen has crossed the 161 mark against the dollar for the first time since 1986.
• Japan reportedly appointed Atsushi Mimura as its top currency diplomat, replacing Masato Kanda, according to Nikkei. Mimura is the director general of the Japanese finance ministry's international bureau.
• Dong Chen, chief Asia strategist and head of Asia research at Swiss private bank Pictet, still expects the yen to stay "fairly weak" despite warnings of intervention from Japanese officials.

The Japanese yen weakened to fresh 38-year lows on Friday, crossing the 161 mark against the dollar for the first time since 1986 and reaching a high of 161.27, according to LSEG data.

The last time the currency was at this level was in December 1986. The currency has struggled and again weakened past the 160 level on Thursday.

The yen has been steadily deprecating since the Bank of Japan ended its negative interest rate policy and scrapped its yield curve control policy in March.

Following the move, the currency crossed the 150 mark against the dollar, reaching 160 in late April before the country's finance ministry intervened.

Japan's finance ministry confirmed that it intervened between April 26 to May 29 to the tune of 9.7885 trillion yen ($62.25 billion).

Dong Chen, chief Asia strategist and head of Asia research at Swiss private bank Pictet, said that he still expects the yen to stay "fairly weak" despite warnings of intervention from Japanese officials.

"To be very honest, actually, I don't think that the Japanese authorities can do a lot about [the] yen, and the market has shown that. Because despite all the verbal interventions, or actual interventions that Japan Ministry of Finance has done over the past, they didn't manage to stop the slide of [the] yen."

Dong explained that this is because the interest rate differential between the U.S. and Japan remains very wide, and this will keep the yen weak unless this differential is depressed "more notably."

The benchmark U.S. federal funds rate stands at 5.25% to 5.5%, while the Bank of Japan's benchmark interest rate is at 0%-0.1%.

Compared to intervention, Dong said rising bond yields in Japan or Federal Reserve rate cuts would be a "more powerful force" for reversing the yen's decline.

Separately, Japan has also reportedly appointed Atsushi Mimura as its top currency diplomat, replacing Masato Kanda, according to Nikkei. Mimura, currently director general of the Japanese finance ministry's international bureau, is expected to take over on July 31.

Nikkei also reported that current vice finance minister Eiji Chatani will be replaced by Hirotsugu Shinkawa, director-general of the finance ministry's budget bureau. This change will take effect on July 5.