Crypto exchange Binanceclosed Bitcoin withdrawals on May 7 due to an alleged overflow of transactions on the Bitcoin network.

The Bitcoin mempool was clogged with over 400,000 transactionswaitingto be processed at the time of writing. The mempool is known as the “waiting area” for incoming transactions before they are verified independently by each node on the network.

Binancetweetedthat BTC withdrawals had resumed after nearly an hour of halting. Outflows on the crypto exchange peaked on May 7,risingto $187 million, according to data from CryptoQuant.

Behind the congestion is believed to be a surge in BRC-20 transactions in the last few days due to memecoins like Pepe (PEPE). The memecoin trading hypedrove Bitcoin transaction fees to their highest pointin two years. On May 3, the total amount of fees paid on the Bitcoin blockchain reached $3.5 million, jumping nearly 400% from late April, Cointelegraph reported.

Developed afterEthereum’s ERC-20 token standard, BRC-20 is an experimental token standard recently introduced that allows users to create and transfer fungible tokens on the Bitcoin blockchain. It is currently becoming a hot spot for meme tokens.

CoinMarketCap’s datashowsthat PEPE’s price has climbed over 263% in the last week. As of writing, however, the memecoin is down over 7% following a 30% drop on May 6 as whalesprofited from Binance's recent listing. Crypto exchanges MEXC Global, Bitget, Gate.ioand Huobilisted PEPE trading pairstwo weeks ago, kicking off the token hype.

Since theintroduction of Dogecoin in 2013, memecoins have become a major part of the cryptocurrency world, making and ruining fortunes alike. Investopediadefines a memecoin as a cryptocurrency represented “with comical or animated memes, that [is] supported by enthusiastic online traders and followers.”